Remove cache thing

Move event up
Self-review
2026-01-18 16:17:26 +01:00 · 2026-01-16 10:07:09 -05:00 · 2026-01-16 09:36:27 -05:00 · 2026-01-15 22:14:56 -05:00 · 2026-01-15 21:55:20 -05:00 · 2026-01-15 19:06:05 -05:00
48 changed files with 2205 additions and 664 deletions
--- a/SECURITY.md
+++ b/SECURITY.md
@@ -6,5 +6,7 @@ As of today, I only support the latest version of ntfy. Please make sure you sta

 ## Reporting a Vulnerability

-Please report severe security issues privately via ntfy@heckel.io, [Discord](https://discord.gg/cT7ECsZj9w),
-or [Matrix](https://matrix.to/#/#ntfy:matrix.org) (my username is `binwiederhier`).
+Please report security vulnerabilities privately via email to [security@mail.ntfy.sh](mailto:security@mail.ntfy.sh).
+
+You can also reach me on [Discord](https://discord.gg/cT7ECsZj9w) or [Matrix](https://matrix.to/#/#ntfy:matrix.org) 
+(my username is `binwiederhier`).
--- a/client/options.go
+++ b/client/options.go
@@ -88,6 +88,11 @@ func WithFilename(filename string) PublishOption {
 	return WithHeader("X-Filename", filename)
 }

+// WithSequenceID sets a sequence ID for the message, allowing updates to existing notifications
+func WithSequenceID(sequenceID string) PublishOption {
+	return WithHeader("X-Sequence-ID", sequenceID)
+}
+
 // WithEmail instructs the server to also send the message to the given e-mail address
 func WithEmail(email string) PublishOption {
 	return WithHeader("X-Email", email)
--- a/cmd/publish.go
+++ b/cmd/publish.go
@@ -34,6 +34,7 @@ var flagsPublish = append(
 	&cli.BoolFlag{Name: "markdown", Aliases: []string{"md"}, EnvVars: []string{"NTFY_MARKDOWN"}, Usage: "Message is formatted as Markdown"},
 	&cli.StringFlag{Name: "template", Aliases: []string{"tpl"}, EnvVars: []string{"NTFY_TEMPLATE"}, Usage: "use templates to transform JSON message body"},
 	&cli.StringFlag{Name: "filename", Aliases: []string{"name", "n"}, EnvVars: []string{"NTFY_FILENAME"}, Usage: "filename for the attachment"},
+	&cli.StringFlag{Name: "sequence-id", Aliases: []string{"sequence_id", "sid", "S"}, EnvVars: []string{"NTFY_SEQUENCE_ID"}, Usage: "sequence ID for updating notifications"},
 	&cli.StringFlag{Name: "file", Aliases: []string{"f"}, EnvVars: []string{"NTFY_FILE"}, Usage: "file to upload as an attachment"},
 	&cli.StringFlag{Name: "email", Aliases: []string{"mail", "e"}, EnvVars: []string{"NTFY_EMAIL"}, Usage: "also send to e-mail address"},
 	&cli.StringFlag{Name: "user", Aliases: []string{"u"}, EnvVars: []string{"NTFY_USER"}, Usage: "username[:password] used to auth against the server"},
@@ -70,6 +71,7 @@ Examples:
  ntfy pub --icon="http://some.tld/icon.png" 'Icon!'      # Send notification with custom icon
  ntfy pub --attach="http://some.tld/file.zip" files      # Send ZIP archive from URL as attachment
  ntfy pub --file=flower.jpg flowers 'Nice!'              # Send image.jpg as attachment
+  ntfy pub -S my-id mytopic 'Update me'                   # Send with sequence ID for updates
  echo 'message' | ntfy publish mytopic                   # Send message from stdin
  ntfy pub -u phil:mypass secret Psst                     # Publish with username/password
  ntfy pub --wait-pid 1234 mytopic                        # Wait for process 1234 to exit before publishing
@@ -101,6 +103,7 @@ func execPublish(c *cli.Context) error {
 	markdown := c.Bool("markdown")
 	template := c.String("template")
 	filename := c.String("filename")
+	sequenceID := c.String("sequence-id")
 	file := c.String("file")
 	email := c.String("email")
 	user := c.String("user")
@@ -154,6 +157,9 @@ func execPublish(c *cli.Context) error {
 	if filename != "" {
 		options = append(options, client.WithFilename(filename))
 	}
+	if sequenceID != "" {
+		options = append(options, client.WithSequenceID(sequenceID))
+	}
 	if email != "" {
 		options = append(options, client.WithEmail(email))
 	}
--- a/docs/config.md
+++ b/docs/config.md
@@ -1013,7 +1013,7 @@ or the root domain:
 === "caddy"
    ```
    # Note that this config is most certainly incomplete. Please help out and let me know what's missing
-    # via Discord/Matrix or in a GitHub issue.
+    # via the contact page (https://ntfy.sh/docs/contact/) or in a GitHub issue.
    # Note: Caddy automatically handles both HTTP and WebSockets with reverse_proxy 

    ntfy.sh, http://nfty.sh {
@@ -1034,7 +1034,7 @@ or the root domain:
    ``` kdl
    // /etc/ferron.kdl	
    // Note that this config is most certainly incomplete. Please help out and let me know what's missing
-    // via Discord/Matrix or in a GitHub issue.
+    // via the contact page (https://ntfy.sh/docs/contact/) or in a GitHub issue.
    // Note: Ferron automatically handles both HTTP and WebSockets with proxy 

    ntfy.sh {
--- a/docs/contact.md
+++ b/docs/contact.md
@@ -0,0 +1,46 @@
+# Contact
+
+This service is run by [Philipp C. Heckel](https://heckel.io). There are several ways to get in touch with me and the 
+ntfy community. Please choose the appropriate channel based on your needs.
+
+## Support
+
+### Community support
+
+For general questions, feature discussions, and community help, please use one of these public channels:
+
+| Channel           | Link                                                                                 | Description                                                |
+|-------------------|--------------------------------------------------------------------------------------|------------------------------------------------------------|
+| **Discord**       | [discord.gg/cT7ECsZj9w](https://discord.gg/cT7ECsZj9w)                               | Real-time chat with the community (I'm `binwiederhier`)    |
+| **Matrix**        | [#ntfy:matrix.org](https://matrix.to/#/#ntfy:matrix.org)                             | Bridged from Discord, same community (I'm `binwiederhier`) |
+| **Matrix Space**  | [#ntfy-space:matrix.org](https://matrix.to/#/#ntfy-space:matrix.org)                 | Matrix space with all ntfy rooms                           |
+| **GitHub Issues** | [github.com/binwiederhier/ntfy/issues](https://github.com/binwiederhier/ntfy/issues) | Bug reports and feature requests                           |
+
+!!! info "Why public channels?"
+    Answering questions in public channels benefits the entire community. Other users can learn from the 
+    discussion, and answers can be referenced later. This is much more scalable than 1-on-1 support.
+
+### Paid support
+
+If you are subscribed to a [ntfy Pro](https://ntfy.sh/#pricing) plan, you are entitled to priority support 
+via the following channels:
+
+| Channel               | Contact                                             | Description                              |
+|-----------------------|-----------------------------------------------------|------------------------------------------|
+| **General Support**   | [support@mail.ntfy.sh](mailto:support@mail.ntfy.sh) | Direct email support for Pro subscribers |
+| **Billing Inquiries** | [billing@mail.ntfy.sh](mailto:support@mail.ntfy.sh) | Inquire about billing issues             |
+| **Discord/Matrix**    | Mention your Pro status                             | Priority responses in community channels |
+
+Please include your ntfy.sh username when contacting support so we can verify your subscription status.
+
+## Security issues
+
+If you discover a security vulnerability, please report it responsibly via [security@mail.ntfy.sh](mailto:security@mail.ntfy.sh). See also: [SECURITY.md](https://github.com/binwiederhier/ntfy/blob/main/SECURITY.md).
+
+## Other inquiries
+
+For questions about our [privacy policy](privacy.md), data handling, or to exercise your data rights 
+(access, deletion, etc.), please email [privacy@mail.ntfy.sh](mailto:privacy@mail.ntfy.sh).
+
+For business inquiries, partnerships, press, or other general questions that don't fit the categories above, please
+use [contact@mail.ntfy.sh](mailto:contact@mail.ntfy.sh).
--- a/docs/contributing.md
+++ b/docs/contributing.md
@@ -0,0 +1,43 @@
+# Contributing
+
+Thank you for your interest in contributing to ntfy! There are many ways to help, whether you're a developer,
+translator, or just an enthusiastic user.
+
+## Code contributions
+
+If you'd like to contribute code to ntfy:
+
+1. Check out the [development guide](develop.md) to set up your environment
+2. Look at [open issues](https://github.com/binwiederhier/ntfy/issues) for ideas, or propose your own
+3. For larger features or architectural changes, please reach out on [Discord/Matrix](contact.md) first to discuss 
+   before investing significant time
+4. Submit a pull request on GitHub
+
+All contributions are welcome, from small bug fixes to major features.
+
+## Translations
+
+Help make ntfy accessible to users around the world! We use Hosted Weblate for translations:
+
+- **Weblate**: [hosted.weblate.org/projects/ntfy](https://hosted.weblate.org/projects/ntfy/)
+
+You can start translating immediately without any coding knowledge.
+
+## Documentation
+
+Found a typo? Want to improve the docs? Documentation contributions are very welcome:
+
+- Edit any page directly on GitHub using the edit button
+- Submit a pull request with your improvements
+
+## Bug reports and feature requests
+
+- **GitHub Issues**: [github.com/binwiederhier/ntfy/issues](https://github.com/binwiederhier/ntfy/issues)
+
+Please search existing issues before creating a new one to avoid duplicates.
+
+## Code of Conduct
+
+Please be respectful and constructive in all interactions. See the 
+[Code of Conduct](https://github.com/binwiederhier/ntfy/blob/main/CODE_OF_CONDUCT.md) for details.
+
--- a/docs/develop.md
+++ b/docs/develop.md
@@ -2,7 +2,7 @@
 Hurray 🥳 🎉, you are interested in writing code for ntfy! **That's awesome.** 😎

 I tried my very best to write up detailed instructions, but if at any point in time you run into issues, don't 
-hesitate to **contact me on [Discord](https://discord.gg/cT7ECsZj9w) or [Matrix](https://matrix.to/#/#ntfy:matrix.org)**.
+hesitate to reach out via one of the channels listed on the [contact page](contact.md).

 ## ntfy server
 The ntfy server source code is available [on GitHub](https://github.com/binwiederhier/ntfy). The codebase for the
@@ -441,6 +441,6 @@ To have instant notifications/better notification delivery when using firebase,
 1. In XCode, find the NTFY app target. **Not** the NSE app target.
 1. Find the Asset/ folder in the project navigator
 1. Drag the `GoogleService-Info.plist` file into the Asset/ folder that you get from the firebase console. It can be 
-   found in the "Project settings" > "General" > "Your apps"  with a button labled "GoogleService-Info.plist"
+   found in the "Project settings" > "General" > "Your apps"  with a button labeled "GoogleService-Info.plist"

 After that, you should be all set!
--- a/docs/faq.md
+++ b/docs/faq.md
@@ -94,11 +94,11 @@ I would be humbled if you helped me carry the server and developer account costs
 appreciated.

 ## Can I email you? Can I DM you on Discord/Matrix?
-While I love chatting on [Discord](https://discord.gg/cT7ECsZj9w), [Matrix](https://matrix.to/#/#ntfy-space:matrix.org), 
-[Lemmy](https://discuss.ntfy.sh/c/ntfy), or [GitHub](https://github.com/binwiederhier/ntfy/issues), I generally 
-**do not respond to emails about ntfy or direct messages** about ntfy, unless you are paying for a 
-[ntfy Pro](https://ntfy.sh/#pricing) plan, or you are inquiring about business opportunities. 
+For community support, please use the public channels listed on the [contact page](contact.md). I generally 
+**do not respond to direct messages** about ntfy, unless you are paying for a [ntfy Pro](https://ntfy.sh/#pricing) 
+plan (see [paid support](contact.md#paid-support)), or you are inquiring about business 
+opportunities (see [other inquiries](contact.md#other-inquiries)).

 I am sorry, but answering individual questions about ntfy on a 1-on-1 basis is not scalable. Answering your questions 
-in the above-mentioned forums benefits others, since I can link to the discussion at a later point in time, or other users
+in public forums benefits others, since I can link to the discussion at a later point in time, or other users
 may be able to help out. I hope you understand.
--- a/docs/integrations.md
+++ b/docs/integrations.md
@@ -181,6 +181,7 @@ I've added a ⭐ to projects or posts that have a significant following, or had
 - [ntfy-heartbeat-monitor](https://codeberg.org/RockWolf/ntfy-heartbeat-monitor) - Application for implementing heartbeat monitoring/alerting by utilizing ntfy
 - [ntfy-bridge](https://github.com/AlexGaudon/ntfy-bridge) - An application to bridge Discord messages (or webhooks) to ntfy.
 - [ntailfy](https://github.com/leukosaima/ntailfy) - ntfy notifications when Tailscale devices connect/disconnect (Go)
+- [BRun](https://github.com/cbrake/brun) - Native Linux automation platform connecting triggers to actions without containers (Go)

 ## Blog + forum posts

--- a/docs/privacy.md
+++ b/docs/privacy.md
@@ -1,12 +1,194 @@
 # Privacy policy

-I love free software, and I'm doing this because it's fun. I have no bad intentions, and **I will
-never monetize or sell your information, and this service and software will always stay free and open.**
+**Last updated:** January 2, 2026

-Neither the server nor the app record any personal information, or share any of the messages and topics with
-any outside service. All data is exclusively used to make the service function properly. The only external service
-I use is Firebase Cloud Messaging (FCM) service, which is required to provide instant Android notifications (see
-[FAQ](faq.md) for details). To avoid FCM altogether, download the F-Droid version.
+This privacy policy describes how ntfy ("we", "us", or "our") collects, uses, and handles your information
+when you use the ntfy.sh service, web app, and mobile applications (Android and iOS).

-For debugging purposes, the ntfy server may temporarily log request paths, remote IP addresses or even topics 
-or messages, though typically this is turned off.
+## Our commitment to privacy
+
+We love free software, and we're doing this because it's fun. We have no bad intentions, and **we will
+never monetize or sell your information**. The ntfy service and software will always stay free and open source.
+If you don't trust us or your messages are sensitive, you can [self-host your own ntfy server](install.md).
+
+## Information we collect
+
+### Account information (optional)
+
+If you create an account on ntfy.sh, we collect:
+
+- **Username** - A unique identifier you choose
+- **Password** - Stored as a secure bcrypt hash (we never store your plaintext password)
+- **Email address** - Only if you subscribe to a paid plan (for billing purposes)
+- **Phone number** - Only if you enable the phone call notification feature (verified via SMS/call)
+
+You can use ntfy without creating an account. Anonymous usage is fully supported.
+
+### Messages and notifications
+
+- **Message content** - Messages you publish are temporarily cached on our servers (default: 12 hours) to support 
+  message polling and to overcome client network disruptions. Messages are deleted after the cache duration expires.
+- **Attachments** - File attachments are temporarily stored (default: 3 hours) and then automatically deleted.
+- **Topic names** - The topic names you publish to or subscribe to are processed by our servers.
+
+### Technical information
+
+- **IP addresses** - Used for rate limiting to prevent abuse. May be temporarily logged for debugging purposes,
+  though this is typically turned off.
+- **Access tokens** - If you create access tokens, we store the token value, an optional label, last access time, 
+  and the IP address of the last access.
+- **Web push subscriptions** - If you enable browser notifications, we store your browser's push subscription 
+  endpoint to deliver notifications.
+
+### Billing information (paid plans only)
+
+If you subscribe to a paid plan, payment processing is handled by Stripe. We store:
+
+- Stripe customer ID
+- Subscription status and billing period
+
+We do not store your credit card numbers or payment details directly. These are handled entirely by Stripe.
+
+## Third-party services
+
+To provide the ntfy.sh service, we use the following third-party services:
+
+### Firebase Cloud Messaging (FCM)
+
+We use Google's Firebase Cloud Messaging to deliver push notifications to Android and iOS devices. When you 
+receive a notification through the mobile apps (Google Play or App Store versions):
+
+- Message metadata and content may be transmitted through Google's FCM infrastructure
+- Google's [privacy policy](https://policies.google.com/privacy) applies to their handling of this data
+
+**To avoid FCM entirely:** Download the [F-Droid version](https://f-droid.org/en/packages/io.heckel.ntfy/) of 
+the Android app and use a self-hosted server, or use the instant delivery feature with your own server.
+
+### Twilio (phone calls)
+
+If you use the phone call notification feature (`X-Call` header), we use Twilio to:
+
+- Make voice calls to your verified phone number
+- Send SMS or voice calls for phone number verification
+
+Your phone number is shared with Twilio to deliver these services. Twilio's 
+[privacy policy](https://www.twilio.com/legal/privacy) applies.
+
+### Amazon SES (email delivery)
+
+If you use the email notification feature (`X-Email` header), we use Amazon Simple Email Service (SES) to 
+deliver emails. The recipient email address and message content are transmitted through Amazon's infrastructure. 
+Amazon's [privacy policy](https://aws.amazon.com/privacy/) applies.
+
+### Stripe (payments)
+
+If you subscribe to a paid plan, payments are processed by Stripe. Your payment information is handled directly 
+by Stripe and is subject to Stripe's [privacy policy](https://stripe.com/privacy).
+
+Note: We have explicitly disabled Stripe's telemetry features in our integration.
+
+### Web push providers
+
+If you enable browser notifications in the ntfy web app, push messages are delivered through your browser 
+vendor's push service:
+
+- Google (Chrome)
+- Mozilla (Firefox)
+- Apple (Safari)
+- Microsoft (Edge)
+
+Your browser's push subscription endpoint is shared with these providers to deliver notifications.
+
+## Mobile applications
+
+### Android app
+
+The Android app is available from two sources:
+
+- **Google Play Store** - Uses Firebase Cloud Messaging for push notifications. Firebase Analytics is 
+  **explicitly disabled** in our app.
+- **F-Droid** - Does not include any Google services or Firebase. Uses a foreground service to maintain 
+  a direct connection to the server.
+
+The Android app stores the following data locally on your device:
+
+- Subscribed topics and their settings
+- Cached notifications
+- User credentials (if you add a server with authentication)
+- Application logs (for debugging, stored locally only)
+
+### iOS app
+
+The iOS app uses Firebase Cloud Messaging (via Apple Push Notification service) to deliver notifications. 
+The app stores the following data locally on your device:
+
+- Subscribed topics
+- Cached notifications
+- User credentials (if configured)
+
+## Web application
+
+The ntfy web app is a static website that stores all data locally in your browser:
+
+- **IndexedDB** - Stores your subscriptions and cached notifications
+- **Local Storage** - Stores your preferences and session information
+
+No cookies are used for tracking. The web app does not have a backend beyond the ntfy API.
+
+## Data retention
+
+| Data type              | Retention period                                  |
+|------------------------|---------------------------------------------------|
+| Messages               | 12 hours (configurable by server operators)       |
+| Attachments            | 3 hours (configurable by server operators)        |
+| User accounts          | Until you delete your account                     |
+| Access tokens          | Until you revoke them or delete your account      |
+| Phone numbers          | Until you remove them or delete your account      |
+| Web push subscriptions | 60 days of inactivity, then automatically removed |
+| Server logs            | Varies; debugging logs are typically temporary    |
+
+## Self-hosting
+
+If you prefer complete control over your data, you can [self-host your own ntfy server](install.md). 
+When self-hosting:
+
+- You control all data storage and retention
+- You can choose whether to use Firebase, Twilio, email delivery, or any other integrations
+- No data is shared with ntfy.sh or any third party (unless you configure those integrations)
+
+The server and all apps are fully open source:
+
+- Server: [github.com/binwiederhier/ntfy](https://github.com/binwiederhier/ntfy)
+- Android app: [github.com/binwiederhier/ntfy-android](https://github.com/binwiederhier/ntfy-android)
+- iOS app: [github.com/binwiederhier/ntfy-ios](https://github.com/binwiederhier/ntfy-ios)
+
+## Data security
+
+- All connections to ntfy.sh are encrypted using TLS/HTTPS
+- Passwords are hashed using bcrypt before storage
+- Access tokens are generated using cryptographically secure random values
+- The server does not log message content by default
+
+## Your rights
+
+You have the right to:
+
+- **Access** - View your account information and data
+- **Delete** - Delete your account and associated data via the web app
+- **Export** - Your messages are available via the API while cached
+
+To delete your account, use the account settings in the web app or contact us.
+
+## Changes to this policy
+
+We may update this privacy policy from time to time. Changes will be posted on this page with an updated 
+"Last updated" date. You may also review all changes in the [Git history](https://github.com/binwiederhier/ntfy/commits/main/docs/privacy.md). 
+
+For significant changes, we may provide additional notice on Discord/Matrix or through the
+[announcements](https://ntfy.sh/announcements) ntfy topic.
+
+## Contact
+
+For privacy-related inquiries, please email [privacy@mail.ntfy.sh](mailto:privacy@mail.ntfy.sh).
+
+For all other contact options, see the [contact page](contact.md).
--- a/docs/publish.md
+++ b/docs/publish.md
@@ -937,6 +937,445 @@ Here's an example with a custom message, tags and a priority:
    file_get_contents('https://ntfy.sh/mywebhook/publish?message=Webhook+triggered&priority=high&tags=warning,skull');
    ```

+## Updating + deleting notifications
+_Supported on:_ :material-android: :material-firefox:
+
+!!! info
+    **This feature is not yet released.** It will be available in ntfy v2.16.x and later and ntfy Android v1.22.x and later.
+
+You can **update, clear (mark as read and dismiss), or delete notifications** that have already been delivered. This is useful for scenarios
+like download progress updates, replacing outdated information, or dismissing notifications that are no longer relevant.
+
+* [Updating notifications](#updating-notifications) will alter the content of an existing notification.
+* [Clearing notifications](#clearing-notifications) will mark them as read and dismiss them from the notification drawer.
+* [Deleting notifications](#deleting-notifications) will remove them from the notification drawer and remove them in the clients as well (if supported).
+
+Here's an example of a download progress notification being updated over time on Android:
+
+<div id="updating-notifications-screenshots" class="screenshots">
+    <a href="../../static/img/android-screenshot-notification-update-1.png"><img src="../../static/img/android-screenshot-notification-update-1.png"/></a>
+    <a href="../../static/img/android-screenshot-notification-update-2.png"><img src="../../static/img/android-screenshot-notification-update-2.png"/></a>
+</div>
+
+To facilitate updating notifications and altering existing notifications, ntfy messages are linked together in a sequence,
+using a **sequence ID**. When a notification is meant to be updated, cleared, or deleted, you publish a new message with the
+same sequence ID and the clients will perform the appropriate action on the existing notification.
+
+Existing ntfy messages will not be updated on the server or in the message cache. Instead, a new message is created that indicates
+the update, clear, or delete action. This append-only behavior ensures that message history remains intact.
+
+### Updating notifications
+To update an existing notification, publish a new message with the same sequence ID. Clients will replace the previous
+notification with the new one. You can either:
+
+1. **Use the message ID**: First publish like normal to `POST /<topic>` without a sequence ID, then use the returned message `id` as the sequence ID for updates
+2. **Use a custom sequence ID**: Publish directly to `POST /<topic>/<sequence_id>` with your own identifier, or use `POST /<topic>` with the 
+   `X-Sequence-ID` header (or any of its aliases: `Sequence-ID` or`SID`)
+
+If you don't know the sequence ID ahead of time, you can publish a message first and then use the returned 
+message `id` to update it. Here's an example:
+
+=== "Command line (curl)"
+    ```bash
+    # First, publish a message and capture the message ID
+    curl -d "Downloading file..." ntfy.sh/mytopic
+    # Returns: {"id":"xE73Iyuabi","time":1673542291,...}
+
+    # Then use the message ID to update it (via URL path)
+    curl -d "Download 50% ..." ntfy.sh/mytopic/xE73Iyuabi
+
+    # Or update using the X-Sequence-ID header
+    curl -H "X-Sequence-ID: xE73Iyuabi" -d "Download complete" ntfy.sh/mytopic
+    ```
+
+=== "ntfy CLI"
+    ```bash
+    # First, publish a message and capture the message ID
+    ntfy pub mytopic "Downloading file..."
+    # Returns: {"id":"xE73Iyuabi","time":1673542291,...}
+
+    # Then use the message ID to update it
+    ntfy pub --sequence-id=xE73Iyuabi mytopic "Download 50% ..."
+
+    # Update again with the same sequence ID
+    ntfy pub -S xE73Iyuabi mytopic "Download complete"
+    ```
+
+=== "HTTP"
+    ``` http
+    # First, publish a message and capture the message ID
+    POST /mytopic HTTP/1.1
+    Host: ntfy.sh
+
+    Downloading file...
+
+    # Returns: {"id":"xE73Iyuabi","time":1673542291,...}
+
+    # Then use the message ID to update it
+    POST /mytopic/xE73Iyuabi HTTP/1.1
+    Host: ntfy.sh
+
+    Download 50% ...
+
+    # Update again with the same sequence ID, this time using the header
+    POST /mytopic HTTP/1.1
+    Host: ntfy.sh
+    X-Sequence-ID: xE73Iyuabi
+
+    Download complete
+    ```
+
+=== "JavaScript"
+    ``` javascript
+    // First, publish and get the message ID
+    const response = await fetch('https://ntfy.sh/mytopic', {
+      method: 'POST',
+      body: 'Downloading file...'
+    });
+    const { id } = await response.json();
+
+    // Update via URL path
+    await fetch(`https://ntfy.sh/mytopic/${id}`, {
+      method: 'POST',
+      body: 'Download 50% ...'
+    });
+
+    // Or update using the X-Sequence-ID header
+    await fetch('https://ntfy.sh/mytopic', {
+      method: 'POST',
+      headers: { 'X-Sequence-ID': id },
+      body: 'Download complete'
+    });
+    ```
+
+=== "Go"
+    ``` go
+    // Publish and parse the response to get the message ID
+    resp, _ := http.Post("https://ntfy.sh/mytopic", "text/plain",
+        strings.NewReader("Downloading file..."))
+    var msg struct { ID string `json:"id"` }
+    json.NewDecoder(resp.Body).Decode(&msg)
+    
+    // Update via URL path
+    http.Post("https://ntfy.sh/mytopic/"+msg.ID, "text/plain",
+        strings.NewReader("Download 50% ..."))
+
+    // Or update using the X-Sequence-ID header
+    req, _ := http.NewRequest("POST", "https://ntfy.sh/mytopic",
+        strings.NewReader("Download complete"))
+    req.Header.Set("X-Sequence-ID", msg.ID)
+    http.DefaultClient.Do(req)
+    ```
+
+=== "PowerShell"
+    ``` powershell
+    # Publish and get the message ID
+    $response = Invoke-RestMethod -Method POST -Uri "https://ntfy.sh/mytopic" -Body "Downloading file..."
+    $messageId = $response.id
+    
+    # Update via URL path
+    Invoke-RestMethod -Method POST -Uri "https://ntfy.sh/mytopic/$messageId" -Body "Download 50% ..."
+
+    # Or update using the X-Sequence-ID header
+    Invoke-RestMethod -Method POST -Uri "https://ntfy.sh/mytopic" `
+        -Headers @{"X-Sequence-ID"=$messageId} -Body "Download complete"
+    ```
+
+=== "Python"
+    ``` python
+    import requests
+    
+    # Publish and get the message ID
+    response = requests.post("https://ntfy.sh/mytopic", data="Downloading file...")
+    message_id = response.json()["id"]
+    
+    # Update via URL path
+    requests.post(f"https://ntfy.sh/mytopic/{message_id}", data="Download 50% ...")
+
+    # Or update using the X-Sequence-ID header
+    requests.post("https://ntfy.sh/mytopic",
+        headers={"X-Sequence-ID": message_id}, data="Download complete")
+    ```
+
+=== "PHP"
+    ``` php-inline
+    // Publish and get the message ID
+    $response = file_get_contents('https://ntfy.sh/mytopic', false, stream_context_create([
+        'http' => ['method' => 'POST', 'content' => 'Downloading file...']
+    ]));
+    $messageId = json_decode($response)->id;
+    
+    // Update via URL path
+    file_get_contents("https://ntfy.sh/mytopic/$messageId", false, stream_context_create([
+        'http' => ['method' => 'POST', 'content' => 'Download 50% ...']
+    ]));
+
+    // Or update using the X-Sequence-ID header
+    file_get_contents('https://ntfy.sh/mytopic', false, stream_context_create([
+        'http' => [
+            'method' => 'POST',
+            'header' => "X-Sequence-ID: $messageId",
+            'content' => 'Download complete'
+        ]
+    ]));
+    ```
+
+You can also use a **custom sequence ID** (e.g., a download ID, job ID, etc.) when publishing the first message. 
+**This is less cumbersome**, since you don't need to capture the message ID first. Just publish directly to
+`/<topic>/<sequence_id>`:
+
+=== "Command line (curl)"
+    ```bash
+    # Publish with a custom sequence ID
+    curl -d "Downloading file..." ntfy.sh/mytopic/my-download-123
+
+    # Update using the same sequence ID (via URL path)
+    curl -d "Download 50% ..." ntfy.sh/mytopic/my-download-123
+
+    # Or update using the X-Sequence-ID header
+    curl -H "X-Sequence-ID: my-download-123" -d "Download complete" ntfy.sh/mytopic
+    ```
+
+=== "ntfy CLI"
+    ```bash
+    # Publish with a sequence ID
+    ntfy pub --sequence-id=my-download-123 mytopic "Downloading file..."
+
+    # Update using the same sequence ID
+    ntfy pub --sequence-id=my-download-123 mytopic "Download 50% ..."
+
+    # Update again
+    ntfy pub -S my-download-123 mytopic "Download complete"
+    ```
+
+=== "HTTP"
+    ``` http
+    # Publish a message with a custom sequence ID
+    POST /mytopic/my-download-123 HTTP/1.1
+    Host: ntfy.sh
+
+    Downloading file...
+
+    # Update again using the X-Sequence-ID header
+    POST /mytopic HTTP/1.1
+    Host: ntfy.sh
+    X-Sequence-ID: my-download-123
+
+    Download complete
+    ```
+
+=== "JavaScript"
+    ``` javascript
+    // First message
+    await fetch('https://ntfy.sh/mytopic/my-download-123', {
+      method: 'POST',
+      body: 'Downloading file...'
+    });
+
+    // Update via URL path
+    await fetch('https://ntfy.sh/mytopic/my-download-123', {
+      method: 'POST',
+      body: 'Download 50% ...'
+    });
+
+    // Or update using the X-Sequence-ID header
+    await fetch('https://ntfy.sh/mytopic', {
+      method: 'POST',
+      headers: { 'X-Sequence-ID': 'my-download-123' },
+      body: 'Download complete'
+    });
+    ```
+
+=== "Go"
+    ``` go
+    // Publish with sequence ID in URL path
+    http.Post("https://ntfy.sh/mytopic/my-download-123", "text/plain",
+        strings.NewReader("Downloading file..."))
+    
+    // Update via URL path
+    http.Post("https://ntfy.sh/mytopic/my-download-123", "text/plain",
+        strings.NewReader("Download 50% ..."))
+
+    // Or update using the X-Sequence-ID header
+    req, _ := http.NewRequest("POST", "https://ntfy.sh/mytopic",
+        strings.NewReader("Download complete"))
+    req.Header.Set("X-Sequence-ID", "my-download-123")
+    http.DefaultClient.Do(req)
+    ```
+
+=== "PowerShell"
+    ``` powershell
+    # Publish with sequence ID
+    Invoke-RestMethod -Method POST -Uri "https://ntfy.sh/mytopic/my-download-123" -Body "Downloading file..."
+    
+    # Update via URL path
+    Invoke-RestMethod -Method POST -Uri "https://ntfy.sh/mytopic/my-download-123" -Body "Download 50% ..."
+
+    # Or update using the X-Sequence-ID header
+    Invoke-RestMethod -Method POST -Uri "https://ntfy.sh/mytopic" `
+        -Headers @{"X-Sequence-ID"="my-download-123"} -Body "Download complete"
+    ```
+
+=== "Python"
+    ``` python
+    import requests
+    
+    # Publish with sequence ID
+    requests.post("https://ntfy.sh/mytopic/my-download-123", data="Downloading file...")
+    
+    # Update via URL path
+    requests.post("https://ntfy.sh/mytopic/my-download-123", data="Download 50% ...")
+
+    # Or update using the X-Sequence-ID header
+    requests.post("https://ntfy.sh/mytopic",
+        headers={"X-Sequence-ID": "my-download-123"}, data="Download complete")
+    ```
+
+=== "PHP"
+    ``` php-inline
+    // Publish with sequence ID
+    file_get_contents('https://ntfy.sh/mytopic/my-download-123', false, stream_context_create([
+        'http' => ['method' => 'POST', 'content' => 'Downloading file...']
+    ]));
+    
+    // Update via URL path
+    file_get_contents('https://ntfy.sh/mytopic/my-download-123', false, stream_context_create([
+        'http' => ['method' => 'POST', 'content' => 'Download 50% ...']
+    ]));
+
+    // Or update using the X-Sequence-ID header
+    file_get_contents('https://ntfy.sh/mytopic', false, stream_context_create([
+        'http' => [
+            'method' => 'POST',
+            'header' => 'X-Sequence-ID: my-download-123',
+            'content' => 'Download complete'
+        ]
+    ]));
+    ```
+
+You can also set the sequence ID via the `sequence-id` [query parameter](#list-of-all-parameters), or when
+[publishing as JSON](#publish-as-json) using the `sequence_id` field.
+
+If the message ID (`id`) and the sequence ID (`sequence_id`) are different, the ntfy server will include the `sequence_id`
+field the response. A sequence of updates may look like this (first example from above):
+
+```json
+{"id":"xE73Iyuabi","time":1673542291,"event":"message","topic":"mytopic","message":"Downloading file..."}
+{"id":"yF84Jzvbcj","time":1673542295,"event":"message","topic":"mytopic","sequence_id":"xE73Iyuabi","message":"Download 50% ..."}
+{"id":"zG95Kawdde","time":1673542300,"event":"message","topic":"mytopic","sequence_id":"xE73Iyuabi","message":"Download complete"}
+```
+
+### Clearing notifications
+Clearing a notification means **marking it as read and dismissing it from the notification drawer**. 
+
+To do this, send a PUT request to the `/<topic>/<sequence_id>/clear` endpoint (or `/<topic>/<sequence_id>/read` as an alias). 
+This will then emit a `message_clear` event that is used by the clients (web app and Android app) to update the read status
+and dismiss the notification.
+
+=== "Command line (curl)"
+    ```bash
+    curl -X PUT ntfy.sh/mytopic/my-download-123/clear
+    ```
+
+=== "HTTP"
+    ``` http
+    PUT /mytopic/my-download-123/clear HTTP/1.1
+    Host: ntfy.sh
+    ```
+
+=== "JavaScript"
+    ``` javascript
+    await fetch('https://ntfy.sh/mytopic/my-download-123/clear', {
+      method: 'PUT'
+    });
+    ```
+
+=== "Go"
+    ``` go
+    req, _ := http.NewRequest("PUT", "https://ntfy.sh/mytopic/my-download-123/clear", nil)
+    http.DefaultClient.Do(req)
+    ```
+
+=== "PowerShell"
+    ``` powershell
+    Invoke-RestMethod -Method PUT -Uri "https://ntfy.sh/mytopic/my-download-123/clear"
+    ```
+
+=== "Python"
+    ``` python
+    requests.put("https://ntfy.sh/mytopic/my-download-123/clear")
+    ```
+
+=== "PHP"
+    ``` php-inline
+    file_get_contents('https://ntfy.sh/mytopic/my-download-123/clear', false, stream_context_create([
+        'http' => ['method' => 'PUT']
+    ]));
+    ```
+
+An example response from the server with the `message_clear` event may look like this:
+
+```json
+{"id":"jkl012","time":1673542305,"event":"message_clear","topic":"mytopic","sequence_id":"my-download-123"}
+```
+
+### Deleting notifications
+Deleting a notification means **removing it from the notification drawer and from the client's database**.
+
+To do this, send a DELETE request to the `/<topic>/<sequence_id>` endpoint. This will emit a `message_delete` event
+that is used by the clients (web app and Android app) to remove the notification entirely.
+
+=== "Command line (curl)"
+    ```bash
+    curl -X DELETE ntfy.sh/mytopic/my-download-123
+    ```
+
+=== "HTTP"
+    ``` http
+    DELETE /mytopic/my-download-123 HTTP/1.1
+    Host: ntfy.sh
+    ```
+
+=== "JavaScript"
+    ``` javascript
+    await fetch('https://ntfy.sh/mytopic/my-download-123', {
+      method: 'DELETE'
+    });
+    ```
+
+=== "Go"
+    ``` go
+    req, _ := http.NewRequest("DELETE", "https://ntfy.sh/mytopic/my-download-123", nil)
+    http.DefaultClient.Do(req)
+    ```
+
+=== "PowerShell"
+    ``` powershell
+    Invoke-RestMethod -Method DELETE -Uri "https://ntfy.sh/mytopic/my-download-123"
+    ```
+
+=== "Python"
+    ``` python
+    requests.delete("https://ntfy.sh/mytopic/my-download-123")
+    ```
+
+=== "PHP"
+    ``` php-inline
+    file_get_contents('https://ntfy.sh/mytopic/my-download-123', false, stream_context_create([
+        'http' => ['method' => 'DELETE']
+    ]));
+    ```
+
+An example response from the server with the `message_delete` event may look like this:
+
+```json
+{"id":"mno345","time":1673542400,"event":"message_delete","topic":"mytopic","sequence_id":"my-download-123"}
+```
+
+!!! info
+    Deleted sequences can be revived by publishing a new message with the same sequence ID. The notification will
+    reappear as a new message.
+
 ## Message templating
 _Supported on:_ :material-android: :material-apple: :material-firefox:

@@ -1418,22 +1857,23 @@ The JSON message format closely mirrors the format of the message you can consum
 (see [JSON message format](subscribe/api.md#json-message-format) for details), but is not exactly identical. Here's an overview of
 all the supported fields:

-| Field      | Required | Type                             | Example                                   | Description                                                           |
-|------------|----------|----------------------------------|-------------------------------------------|-----------------------------------------------------------------------|
-| `topic`    | ✔️       | *string*                         | `topic1`                                  | Target topic name                                                     |
-| `message`  | -        | *string*                         | `Some message`                            | Message body; set to `triggered` if empty or not passed               |
-| `title`    | -        | *string*                         | `Some title`                              | Message [title](#message-title)                                       |
-| `tags`     | -        | *string array*                   | `["tag1","tag2"]`                         | List of [tags](#tags-emojis) that may or not map to emojis            |
-| `priority` | -        | *int (one of: 1, 2, 3, 4, or 5)* | `4`                                       | Message [priority](#message-priority) with 1=min, 3=default and 5=max |
-| `actions`  | -        | *JSON array*                     | *(see [action buttons](#action-buttons))* | Custom [user action buttons](#action-buttons) for notifications       |
-| `click`    | -        | *URL*                            | `https://example.com`                     | Website opened when notification is [clicked](#click-action)          |
-| `attach`   | -        | *URL*                            | `https://example.com/file.jpg`            | URL of an attachment, see [attach via URL](#attach-file-from-a-url)   |
-| `markdown` | -        | *bool*                           | `true`                                    | Set to true if the `message` is Markdown-formatted                    |
-| `icon`     | -        | *string*                         | `https://example.com/icon.png`            | URL to use as notification [icon](#icons)                             |
-| `filename` | -        | *string*                         | `file.jpg`                                | File name of the attachment                                           |
-| `delay`    | -        | *string*                         | `30min`, `9am`                            | Timestamp or duration for delayed delivery                            |
-| `email`    | -        | *e-mail address*                 | `phil@example.com`                        | E-mail address for e-mail notifications                               |
-| `call`     | -        | *phone number or 'yes'*          | `+1222334444` or `yes`                    | Phone number to use for [voice call](#phone-calls)                    |
+| Field         | Required | Type                             | Example                                   | Description                                                                               |
+|---------------|----------|----------------------------------|-------------------------------------------|-------------------------------------------------------------------------------------------|
+| `topic`       | ✔️       | *string*                         | `topic1`                                  | Target topic name                                                                         |
+| `message`     | -        | *string*                         | `Some message`                            | Message body; set to `triggered` if empty or not passed                                   |
+| `title`       | -        | *string*                         | `Some title`                              | Message [title](#message-title)                                                           |
+| `tags`        | -        | *string array*                   | `["tag1","tag2"]`                         | List of [tags](#tags-emojis) that may or not map to emojis                                |
+| `priority`    | -        | *int (one of: 1, 2, 3, 4, or 5)* | `4`                                       | Message [priority](#message-priority) with 1=min, 3=default and 5=max                     |
+| `actions`     | -        | *JSON array*                     | *(see [action buttons](#action-buttons))* | Custom [user action buttons](#action-buttons) for notifications                           |
+| `click`       | -        | *URL*                            | `https://example.com`                     | Website opened when notification is [clicked](#click-action)                              |
+| `attach`      | -        | *URL*                            | `https://example.com/file.jpg`            | URL of an attachment, see [attach via URL](#attach-file-from-a-url)                       |
+| `markdown`    | -        | *bool*                           | `true`                                    | Set to true if the `message` is Markdown-formatted                                        |
+| `icon`        | -        | *string*                         | `https://example.com/icon.png`            | URL to use as notification [icon](#icons)                                                 |
+| `filename`    | -        | *string*                         | `file.jpg`                                | File name of the attachment                                                               |
+| `delay`       | -        | *string*                         | `30min`, `9am`                            | Timestamp or duration for delayed delivery                                                |
+| `email`       | -        | *e-mail address*                 | `phil@example.com`                        | E-mail address for e-mail notifications                                                   |
+| `call`        | -        | *phone number or 'yes'*          | `+1222334444` or `yes`                    | Phone number to use for [voice call](#phone-calls)                                        |
+| `sequence_id` | -        | *string*                         | `my-sequence-123`                         | Sequence ID for [updating/deleting notifications](#updating-deleting-notifications)   |

 ## Action buttons
 _Supported on:_ :material-android: :material-apple: :material-firefox:
@@ -3931,6 +4371,7 @@ table in their canonical form.
 |-----------------|--------------------------------------------|-----------------------------------------------------------------------------------------------|
 | `X-Message`     | `Message`, `m`                             | Main body of the message as shown in the notification                                         |
 | `X-Title`       | `Title`, `t`                               | [Message title](#message-title)                                                               |
+| `X-Sequence-ID` | `Sequence-ID`, `SID`                       | [Sequence ID](#updating-deleting-notifications) for updating/clearing/deleting notifications  |
 | `X-Priority`    | `Priority`, `prio`, `p`                    | [Message priority](#message-priority)                                                         |
 | `X-Tags`        | `Tags`, `Tag`, `ta`                        | [Tags and emojis](#tags-emojis)                                                               |
 | `X-Delay`       | `Delay`, `X-At`, `At`, `X-In`, `In`        | Timestamp or duration for [delayed delivery](#scheduled-delivery)                             |
--- a/docs/publish/template-functions.md
+++ b/docs/publish/template-functions.md
@@ -1174,7 +1174,7 @@ keys $myDict | sortAlpha
 ```

 When supplying multiple dictionaries, the keys will be concatenated. Use the `uniq`
-function along with `sortAlpha` to get a unqiue, sorted list of keys.
+function along with `sortAlpha` to get a unique, sorted list of keys.

 ```
 keys $myDict $myOtherDict | uniq | sortAlpha
--- a/docs/releases.md
+++ b/docs/releases.md
@@ -4,14 +4,41 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release

 ## Current stable releases

-| Component                                | Version | Release date |
-|------------------------------------------|---------|--------------|
-| ntfy server                              | v2.15.0 | Nov 16, 2025 |
-| ntfy Android app (_is being rolled out_) | v1.20.0 | Dec 28, 2025 |
-| ntfy iOS app                             | v1.3    | Nov 26, 2023 |
+| Component        | Version | Release date |
+|------------------|---------|--------------|
+| ntfy server      | v2.15.0 | Nov 16, 2025 |
+| ntfy Android app | v1.21.1 | Jan 6, 2025  |
+| ntfy iOS app     | v1.3    | Nov 26, 2023 |

 Please check out the release notes for [upcoming releases](#not-released-yet) below.

+## ntfy Android app v1.21.1
+Released January 6, 2026
+
+This is the first feature release in a long time. After all the SDK updates, fixes to comply with the Google Play policies
+and the framework updates, this release ships a lot of highly requested features: Sending messages through the app (WhatsApp-style),
+support for passing headers to your proxy, an in-app language switcher, and more.
+
+If you are waiting for a feature, please 👍 the corresponding [GitHub issue](https://github.com/binwiederhier/ntfy/issues?q=is%3Aissue%20state%3Aopen%20sort%3Areactions-%2B1-desc).
+If you like ntfy, please consider purchasing [ntfy Pro](https://ntfy.sh/app) to support us.
+
+**Features:**
+
+* Allow publishing messages through the message bar and publish dialog ([#98](https://github.com/binwiederhier/ntfy/issues/98), [ntfy-android#144](https://github.com/binwiederhier/ntfy-android/pull/144))
+* Define custom HTTP headers to support authenticated proxies, tunnels and SSO ([ntfy-android#116](https://github.com/binwiederhier/ntfy-android/issues/116), [#1018](https://github.com/binwiederhier/ntfy/issues/1018), [ntfy-android#132](https://github.com/binwiederhier/ntfy-android/pull/132), [ntfy-android#146](https://github.com/binwiederhier/ntfy-android/pull/146), thanks to [@CrazyWolf13](https://github.com/CrazyWolf13))
+* Implement UnifiedPush "raise to foreground" requirement ([ntfy-android#98](https://github.com/binwiederhier/ntfy-android/pull/98), [ntfy-android#148](https://github.com/binwiederhier/ntfy-android/pull/148), thanks to [@p1gp1g](https://github.com/p1gp1g))
+* Language selector to allow overriding the system language ([#1508](https://github.com/binwiederhier/ntfy/issues/1508), [ntfy-android#145](https://github.com/binwiederhier/ntfy-android/pull/145), thanks to [@hudsonm62](https://github.com/hudsonm62) for reporting)
+* Highlight phone numbers and email addresses in notifications ([#957](https://github.com/binwiederhier/ntfy/issues/957), [ntfy-android#71](https://github.com/binwiederhier/ntfy-android/pull/71), thanks to [@brennenputh](https://github.com/brennenputh), and [@XylenSky](https://github.com/XylenSky) for reporting)
+* Support for port and display name in [ntfy://](subscribe/phone.md#ntfy-links) links ([ntfy-android#130](https://github.com/binwiederhier/ntfy-android/pull/130), thanks to [@godovski](https://github.com/godovski))
+
+**Bug fixes + maintenance:**
+
+* Add support for (technically incorrect) 'image/jpg' MIME type ([ntfy-android#142](https://github.com/binwiederhier/ntfy-android/pull/142), thanks to [@Murilobeluco](https://github.com/Murilobeluco))
+* Unify "copy to clipboard" notifications, use Android 13 style ([ntfy-android#61](https://github.com/binwiederhier/ntfy-android/pull/61), thanks to [@thgoebel](https://github.com/thgoebel))
+* Fix crash in user add dialog (onAddUser)
+* Fix ForegroundServiceDidNotStartInTimeException (attempt 2, see [#1520](https://github.com/binwiederhier/ntfy/issues/1520))
+* Hide "Exact alarms" setting if battery optimization exemption has been granted ([#1456](https://github.com/binwiederhier/ntfy/issues/1456), thanks for reporting [@HappyLer](https://github.com/HappyLer))
+
 ## ntfy Android app v1.20.0
 Released December 28, 2025

@@ -1572,18 +1599,32 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release

 ## Not released yet

-### ntfy Android app v1.21.x
+### ntfy server v2.16.x (UNRELEASED)

 **Features:**

-* Allow publishing messages through the message bar and publish dialog ([#98](https://github.com/binwiederhier/ntfy/issues/98), [ntfy-android#144](https://github.com/binwiederhier/ntfy-android/pull/144))
-* Define custom HTTP headers to support authenticated proxies, tunnels and SSO ([ntfy-android#116](https://github.com/binwiederhier/ntfy-android/issues/116), [#1018](https://github.com/binwiederhier/ntfy/issues/1018), [ntfy-android#132](https://github.com/binwiederhier/ntfy-android/pull/132), [ntfy-android#146](https://github.com/binwiederhier/ntfy-android/pull/146), thanks to [@CrazyWolf13](https://github.com/CrazyWolf13))
-* Implement UnifiedPush "raise to foreground" requirement ([ntfy-android#98](https://github.com/binwiederhier/ntfy-android/pull/98), [ntfy-android#148](https://github.com/binwiederhier/ntfy-android/pull/148), thanks to [@p1gp1g](https://github.com/p1gp1g))
-* Language selector to allow overriding the system language ([#1508](https://github.com/binwiederhier/ntfy/issues/1508), [ntfy-android#145](https://github.com/binwiederhier/ntfy-android/pull/145), thanks to [@hudsonm62](https://github.com/hudsonm62) for reporting)
-* Highlight phone numbers and email addresses in notifications ([#957](https://github.com/binwiederhier/ntfy/issues/957), [ntfy-android#71](https://github.com/binwiederhier/ntfy-android/pull/71), thanks to [@brennenputh](https://github.com/brennenputh), and [@XylenSky](https://github.com/XylenSky) for reporting)
-* Support for port and display name in [ntfy://](subscribe/phone.md#ntfy-links) links ([ntfy-android#130](https://github.com/binwiederhier/ntfy-android/pull/130), thanks to [@godovski](https://github.com/godovski))
+* Support for [updating and deleting notifications](publish.md#updating-deleting-notifications) 
+  ([#303](https://github.com/binwiederhier/ntfy/issues/303), [#1536](https://github.com/binwiederhier/ntfy/pull/1536),
+  [ntfy-android#151](https://github.com/binwiederhier/ntfy-android/pull/151), thanks to [@wunter8](https://github.com/wunter8)
+  for the initial implementation)
+
+### ntfy Android app v1.22.x (UNRELEASED)
+
+**Features:**
+
+* Support for [updating and deleting notifications](publish.md#updating-deleting-notifications)
+  ([#303](https://github.com/binwiederhier/ntfy/issues/303), [#1536](https://github.com/binwiederhier/ntfy/pull/1536),
+  [ntfy-android#151](https://github.com/binwiederhier/ntfy-android/pull/151), thanks to [@wunter8](https://github.com/wunter8)
+  for the initial implementation)
+* Support for self-signed certs and client certs for mTLS ([#215](https://github.com/binwiederhier/ntfy/issues/215),
+  [#530](https://github.com/binwiederhier/ntfy/issues/530), [ntfy-android#149](https://github.com/binwiederhier/ntfy-android/pull/149),
+  thanks to [@cyb3rko](https://github.com/cyb3rko) for reviewing)
+* Connection error dialog to help diagnose connection issues

 **Bug fixes + maintenance:**

-* Add support for (technically incorrect) 'image/jpg' MIME type ([ntfy-android#142](https://github.com/binwiederhier/ntfy-android/pull/142), thanks to [@Murilobeluco](https://github.com/Murilobeluco))
-* Unify "copy to clipboard" notifications, use Android 13 style ([ntfy-android#61](https://github.com/binwiederhier/ntfy-android/pull/61), thanks to [@thgoebel](https://github.com/thgoebel))
+* Use server-specific user for attachment downloads ([#1529](https://github.com/binwiederhier/ntfy/issues/1529),
+  thanks to [@ManInDark](https://github.com/ManInDark) for reporting and testing)
+* Fix crash in sharing dialog (thanks to [@rogeliodh](https://github.com/rogeliodh))
+* Fix crash when exiting multi-delete in detail view
+* Fix potential crashes with icon downloader and backuper
--- a/docs/static/css/extra.css
+++ b/docs/static/css/extra.css
@@ -1,10 +1,10 @@
 :root > * {
-    --md-primary-fg-color:        #338574;
+    --md-primary-fg-color: #338574;
    --md-primary-fg-color--light: #338574;
-    --md-primary-fg-color--dark:  #338574;
-    --md-footer-bg-color:         #353744;
-    --md-text-font:               "Roboto";
-    --md-code-font:               "Roboto Mono";
+    --md-primary-fg-color--dark: #338574;
+    --md-footer-bg-color: #353744;
+    --md-text-font: "Roboto";
+    --md-code-font: "Roboto Mono";
 }

 .md-header__button.md-logo :is(img, svg) {
@@ -34,7 +34,7 @@ figure img, figure video {
 }

 header {
-    background: linear-gradient(150deg, rgba(51,133,116,1) 0%, rgba(86,189,168,1) 100%);
+    background: linear-gradient(150deg, rgba(51, 133, 116, 1) 0%, rgba(86, 189, 168, 1) 100%);
 }

 body[data-md-color-scheme="default"] header {
@@ -93,7 +93,7 @@ figure video {

 .screenshots img {
    max-height: 230px;
-    max-width: 300px;
+    max-width: 350px;
    margin: 3px;
    border-radius: 5px;
    filter: drop-shadow(2px 2px 2px #ddd);
@@ -107,7 +107,7 @@ figure video {
    opacity: 0;
    visibility: hidden;
    position: fixed;
-    left:0;
+    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
@@ -119,7 +119,7 @@ figure video {
 }

 .lightbox.show {
-    background-color: rgba(0,0,0, 0.75);
+    background-color: rgba(0, 0, 0, 0.75);
    opacity: 1;
    visibility: visible;
    z-index: 1000;
--- a/docs/static/img/android-screenshot-notification-update-1.png
+++ b/docs/static/img/android-screenshot-notification-update-1.png
--- a/docs/static/img/android-screenshot-notification-update-2.png
+++ b/docs/static/img/android-screenshot-notification-update-2.png
--- a/docs/subscribe/api.md
+++ b/docs/subscribe/api.md
@@ -324,20 +324,21 @@ format of the message. It's very straight forward:

 **Message**:

-| Field        | Required | Type                                              | Example                                               | Description                                                                                                                          |
-|--------------|----------|---------------------------------------------------|-------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|
-| `id`         | ✔️       | *string*                                          | `hwQ2YpKdmg`                                          | Randomly chosen message identifier                                                                                                   |
-| `time`       | ✔️       | *number*                                          | `1635528741`                                          | Message date time, as Unix time stamp                                                                                                |  
-| `expires`    | (✔)️     | *number*                                          | `1673542291`                                          | Unix time stamp indicating when the message will be deleted, not set if `Cache: no` is sent                                          |  
-| `event`      | ✔️       | `open`, `keepalive`, `message`, or `poll_request` | `message`                                             | Message type, typically you'd be only interested in `message`                                                                        |
-| `topic`      | ✔️       | *string*                                          | `topic1,topic2`                                       | Comma-separated list of topics the message is associated with; only one for all `message` events, but may be a list in `open` events |
-| `message`    | -        | *string*                                          | `Some message`                                        | Message body; always present in `message` events                                                                                     |
-| `title`      | -        | *string*                                          | `Some title`                                          | Message [title](../publish.md#message-title); if not set defaults to `ntfy.sh/<topic>`                                               |
-| `tags`       | -        | *string array*                                    | `["tag1","tag2"]`                                     | List of [tags](../publish.md#tags-emojis) that may or not map to emojis                                                              |
-| `priority`   | -        | *1, 2, 3, 4, or 5*                                | `4`                                                   | Message [priority](../publish.md#message-priority) with 1=min, 3=default and 5=max                                                   |
-| `click`      | -        | *URL*                                             | `https://example.com`                                 | Website opened when notification is [clicked](../publish.md#click-action)                                                            |
-| `actions`    | -        | *JSON array*                                      | *see [actions buttons](../publish.md#action-buttons)* | [Action buttons](../publish.md#action-buttons) that can be displayed in the notification                                             |
-| `attachment` | -        | *JSON object*                                     | *see below*                                           | Details about an attachment (name, URL, size, ...)                                                                                   |
+| Field         | Required | Type                                                                            | Example                                               | Description                                                                                                                          |
+|---------------|----------|---------------------------------------------------------------------------------|-------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|
+| `id`          | ✔️       | *string*                                                                        | `hwQ2YpKdmg`                                          | Randomly chosen message identifier                                                                                                   |
+| `time`        | ✔️       | *number*                                                                        | `1635528741`                                          | Message date time, as Unix time stamp                                                                                                |  
+| `expires`     | (✔)️     | *number*                                                                        | `1673542291`                                          | Unix time stamp indicating when the message will be deleted, not set if `Cache: no` is sent                                          |  
+| `event`       | ✔️       | `open`, `keepalive`, `message`, `message_delete`, `message_clear`, `poll_request` | `message`                                             | Message type, typically you'd be only interested in `message`                                                                        |
+| `topic`       | ✔️       | *string*                                                                        | `topic1,topic2`                                       | Comma-separated list of topics the message is associated with; only one for all `message` events, but may be a list in `open` events |
+| `sequence_id` | -        | *string*                                                                        | `my-sequence-123`                                     | Sequence ID for [updating/deleting notifications](../publish.md#updating-deleting-notifications)                                 |
+| `message`     | -        | *string*                                                                        | `Some message`                                        | Message body; always present in `message` events                                                                                     |
+| `title`       | -        | *string*                                                                        | `Some title`                                          | Message [title](../publish.md#message-title); if not set defaults to `ntfy.sh/<topic>`                                               |
+| `tags`        | -        | *string array*                                                                  | `["tag1","tag2"]`                                     | List of [tags](../publish.md#tags-emojis) that may or not map to emojis                                                              |
+| `priority`    | -        | *1, 2, 3, 4, or 5*                                                              | `4`                                                   | Message [priority](../publish.md#message-priority) with 1=min, 3=default and 5=max                                                   |
+| `click`       | -        | *URL*                                                                           | `https://example.com`                                 | Website opened when notification is [clicked](../publish.md#click-action)                                                            |
+| `actions`     | -        | *JSON array*                                                                    | *see [actions buttons](../publish.md#action-buttons)* | [Action buttons](../publish.md#action-buttons) that can be displayed in the notification                                             |
+| `attachment`  | -        | *JSON object*                                                                   | *see below*                                           | Details about an attachment (name, URL, size, ...)                                                                                   |

 **Attachment** (part of the message, see [attachments](../publish.md#attachments) for details):

--- a/docs/subscribe/phone.md
+++ b/docs/subscribe/phone.md
@@ -100,7 +100,7 @@ The reason for this is [Firebase Cloud Messaging (FCM)](https://firebase.google.
 notifications. Firebase is overall pretty bad at delivering messages in time, but on Android, most apps are stuck with it.

 The ntfy Android app uses Firebase only for the main host `ntfy.sh`, and only in the Google Play flavor of the app.
-It won't use Firebase for any self-hosted servers, and not at all in the the F-Droid flavor.
+It won't use Firebase for any self-hosted servers, and not at all in the F-Droid flavor.

 ## Share to topic
 _Supported on:_ :material-android:
--- a/docs/troubleshooting.md
+++ b/docs/troubleshooting.md
@@ -1,7 +1,7 @@
 # Troubleshooting
 This page lists a few suggestions of what to do when things don't work as expected. This is not a complete list. 
-If this page does not help, feel free to drop by the [Discord](https://discord.gg/cT7ECsZj9w) or [Matrix](https://matrix.to/#/#ntfy:matrix.org)
-and ask there. We're happy to help.
+If this page does not help, feel free to reach out via one of the channels listed on the [contact page](contact.md).
+We're happy to help.

 ## ntfy server
 If you host your own ntfy server, and you're having issues with any component, it is always helpful to enable debugging/tracing
--- a/go.mod
+++ b/go.mod
@@ -6,22 +6,22 @@ toolchain go1.24.5

 require (
 	cloud.google.com/go/firestore v1.20.0 // indirect
-	cloud.google.com/go/storage v1.58.0 // indirect
+	cloud.google.com/go/storage v1.59.0 // indirect
 	github.com/BurntSushi/toml v1.6.0 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.7 // indirect
 	github.com/emersion/go-smtp v0.18.0
 	github.com/gabriel-vasile/mimetype v1.4.12
 	github.com/gorilla/websocket v1.5.3
-	github.com/mattn/go-sqlite3 v1.14.32
+	github.com/mattn/go-sqlite3 v1.14.33
 	github.com/olebedev/when v1.1.0
 	github.com/stretchr/testify v1.11.1
 	github.com/urfave/cli/v2 v2.27.7
-	golang.org/x/crypto v0.46.0
+	golang.org/x/crypto v0.47.0
 	golang.org/x/oauth2 v0.34.0 // indirect
 	golang.org/x/sync v0.19.0
-	golang.org/x/term v0.38.0
+	golang.org/x/term v0.39.0
 	golang.org/x/time v0.14.0
-	google.golang.org/api v0.258.0
+	google.golang.org/api v0.259.0
 	gopkg.in/yaml.v2 v2.4.0
 )

@@ -35,7 +35,7 @@ require (
 	github.com/microcosm-cc/bluemonday v1.0.27
 	github.com/prometheus/client_golang v1.23.2
 	github.com/stripe/stripe-go/v74 v74.30.0
-	golang.org/x/text v0.32.0
+	golang.org/x/text v0.33.0
 )

 require (
@@ -45,7 +45,7 @@ require (
 	cloud.google.com/go/auth/oauth2adapt v0.2.8 // indirect
 	cloud.google.com/go/compute/metadata v0.9.0 // indirect
 	cloud.google.com/go/iam v1.5.3 // indirect
-	cloud.google.com/go/longrunning v0.7.0 // indirect
+	cloud.google.com/go/longrunning v0.8.0 // indirect
 	cloud.google.com/go/monitoring v1.24.3 // indirect
 	github.com/AlekSi/pointer v1.2.0 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.30.0 // indirect
@@ -69,14 +69,14 @@ require (
 	github.com/golang/protobuf v1.5.4 // indirect
 	github.com/google/s2a-go v0.1.9 // indirect
 	github.com/google/uuid v1.6.0 // indirect
-	github.com/googleapis/enterprise-certificate-proxy v0.3.7 // indirect
+	github.com/googleapis/enterprise-certificate-proxy v0.3.9 // indirect
 	github.com/googleapis/gax-go/v2 v2.16.0 // indirect
 	github.com/gorilla/css v1.0.1 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/prometheus/client_model v0.6.2 // indirect
-	github.com/prometheus/common v0.67.4 // indirect
+	github.com/prometheus/common v0.67.5 // indirect
 	github.com/prometheus/procfs v0.19.2 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/spiffe/go-spiffe/v2 v2.6.0 // indirect
@@ -92,13 +92,13 @@ require (
 	go.opentelemetry.io/otel/sdk/metric v1.39.0 // indirect
 	go.opentelemetry.io/otel/trace v1.39.0 // indirect
 	go.yaml.in/yaml/v2 v2.4.3 // indirect
-	golang.org/x/net v0.48.0 // indirect
-	golang.org/x/sys v0.39.0 // indirect
+	golang.org/x/net v0.49.0 // indirect
+	golang.org/x/sys v0.40.0 // indirect
 	google.golang.org/appengine/v2 v2.0.6 // indirect
-	google.golang.org/genproto v0.0.0-20251213004720-97cd9d5aeac2 // indirect
-	google.golang.org/genproto/googleapis/api v0.0.0-20251213004720-97cd9d5aeac2 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20251213004720-97cd9d5aeac2 // indirect
-	google.golang.org/grpc v1.77.0 // indirect
+	google.golang.org/genproto v0.0.0-20260112192933-99fd39fd28a9 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20260112192933-99fd39fd28a9 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20260112192933-99fd39fd28a9 // indirect
+	google.golang.org/grpc v1.78.0 // indirect
 	google.golang.org/protobuf v1.36.11 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
--- a/go.sum
+++ b/go.sum
@@ -14,12 +14,12 @@ cloud.google.com/go/iam v1.5.3 h1:+vMINPiDF2ognBJ97ABAYYwRgsaqxPbQDlMnbHMjolc=
 cloud.google.com/go/iam v1.5.3/go.mod h1:MR3v9oLkZCTlaqljW6Eb2d3HGDGK5/bDv93jhfISFvU=
 cloud.google.com/go/logging v1.13.1 h1:O7LvmO0kGLaHY/gq8cV7T0dyp6zJhYAOtZPX4TF3QtY=
 cloud.google.com/go/logging v1.13.1/go.mod h1:XAQkfkMBxQRjQek96WLPNze7vsOmay9H5PqfsNYDqvw=
-cloud.google.com/go/longrunning v0.7.0 h1:FV0+SYF1RIj59gyoWDRi45GiYUMM3K1qO51qoboQT1E=
-cloud.google.com/go/longrunning v0.7.0/go.mod h1:ySn2yXmjbK9Ba0zsQqunhDkYi0+9rlXIwnoAf+h+TPY=
+cloud.google.com/go/longrunning v0.8.0 h1:LiKK77J3bx5gDLi4SMViHixjD2ohlkwBi+mKA7EhfW8=
+cloud.google.com/go/longrunning v0.8.0/go.mod h1:UmErU2Onzi+fKDg2gR7dusz11Pe26aknR4kHmJJqIfk=
 cloud.google.com/go/monitoring v1.24.3 h1:dde+gMNc0UhPZD1Azu6at2e79bfdztVDS5lvhOdsgaE=
 cloud.google.com/go/monitoring v1.24.3/go.mod h1:nYP6W0tm3N9H/bOw8am7t62YTzZY+zUeQ+Bi6+2eonI=
-cloud.google.com/go/storage v1.58.0 h1:PflFXlmFJjG/nBeR9B7pKddLQWaFaRWx4uUi/LyNxxo=
-cloud.google.com/go/storage v1.58.0/go.mod h1:cMWbtM+anpC74gn6qjLh+exqYcfmB9Hqe5z6adx+CLI=
+cloud.google.com/go/storage v1.59.0 h1:9p3yDzEN9Vet4JnbN90FECIw6n4FCXcKBK1scxtQnw8=
+cloud.google.com/go/storage v1.59.0/go.mod h1:cMWbtM+anpC74gn6qjLh+exqYcfmB9Hqe5z6adx+CLI=
 cloud.google.com/go/trace v1.11.7 h1:kDNDX8JkaAG3R2nq1lIdkb7FCSi1rCmsEtKVsty7p+U=
 cloud.google.com/go/trace v1.11.7/go.mod h1:TNn9d5V3fQVf6s4SCveVMIBS2LJUqo73GACmq/Tky0s=
 firebase.google.com/go/v4 v4.18.0 h1:S+g0P72oDGqOaG4wlLErX3zQmU9plVdu7j+Bc3R1qFw=
@@ -96,8 +96,8 @@ github.com/google/s2a-go v0.1.9 h1:LGD7gtMgezd8a/Xak7mEWL0PjoTQFvpRudN895yqKW0=
 github.com/google/s2a-go v0.1.9/go.mod h1:YA0Ei2ZQL3acow2O62kdp9UlnvMmU7kA6Eutn0dXayM=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/googleapis/enterprise-certificate-proxy v0.3.7 h1:zrn2Ee/nWmHulBx5sAVrGgAa0f2/R35S4DJwfFaUPFQ=
-github.com/googleapis/enterprise-certificate-proxy v0.3.7/go.mod h1:MkHOF77EYAE7qfSuSS9PU6g4Nt4e11cnsDUowfwewLA=
+github.com/googleapis/enterprise-certificate-proxy v0.3.9 h1:TOpi/QG8iDcZlkQlGlFUti/ZtyLkliXvHDcyUIMuFrU=
+github.com/googleapis/enterprise-certificate-proxy v0.3.9/go.mod h1:MkHOF77EYAE7qfSuSS9PU6g4Nt4e11cnsDUowfwewLA=
 github.com/googleapis/gax-go/v2 v2.16.0 h1:iHbQmKLLZrexmb0OSsNGTeSTS0HO4YvFOG8g5E4Zd0Y=
 github.com/googleapis/gax-go/v2 v2.16.0/go.mod h1:o1vfQjjNZn4+dPnRdl/4ZD7S9414Y4xA+a/6Icj6l14=
 github.com/gorilla/css v1.0.1 h1:ntNaBIghp6JmvWnxbZKANoLyuXTPZ4cAMlo6RyhlbO8=
@@ -112,8 +112,8 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
-github.com/mattn/go-sqlite3 v1.14.32 h1:JD12Ag3oLy1zQA+BNn74xRgaBbdhbNIDYvQUEuuErjs=
-github.com/mattn/go-sqlite3 v1.14.32/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
+github.com/mattn/go-sqlite3 v1.14.33 h1:A5blZ5ulQo2AtayQ9/limgHEkFreKj1Dv226a1K73s0=
+github.com/mattn/go-sqlite3 v1.14.33/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
 github.com/microcosm-cc/bluemonday v1.0.27 h1:MpEUotklkwCSLeH+Qdx1VJgNqLlpY2KXwXFM08ygZfk=
 github.com/microcosm-cc/bluemonday v1.0.27/go.mod h1:jFi9vgW+H7c3V0lb6nR74Ib/DIB5OBs92Dimizgw2cA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
@@ -131,8 +131,8 @@ github.com/prometheus/client_golang v1.23.2 h1:Je96obch5RDVy3FDMndoUsjAhG5Edi49h
 github.com/prometheus/client_golang v1.23.2/go.mod h1:Tb1a6LWHB3/SPIzCoaDXI4I8UHKeFTEQ1YCr+0Gyqmg=
 github.com/prometheus/client_model v0.6.2 h1:oBsgwpGs7iVziMvrGhE53c/GrLUsZdHnqNwqPLxwZyk=
 github.com/prometheus/client_model v0.6.2/go.mod h1:y3m2F6Gdpfy6Ut/GBsUqTWZqCUvMVzSfMLjcu6wAwpE=
-github.com/prometheus/common v0.67.4 h1:yR3NqWO1/UyO1w2PhUvXlGQs/PtFmoveVO0KZ4+Lvsc=
-github.com/prometheus/common v0.67.4/go.mod h1:gP0fq6YjjNCLssJCQp0yk4M8W6ikLURwkdd/YKtTbyI=
+github.com/prometheus/common v0.67.5 h1:pIgK94WWlQt1WLwAC5j2ynLaBRDiinoAb86HZHTUGI4=
+github.com/prometheus/common v0.67.5/go.mod h1:SjE/0MzDEEAyrdr5Gqc6G+sXI67maCxzaT3A2+HqjUw=
 github.com/prometheus/procfs v0.19.2 h1:zUMhqEW66Ex7OXIiDkll3tl9a1ZdilUOd/F6ZXw4Vws=
 github.com/prometheus/procfs v0.19.2/go.mod h1:M0aotyiemPhBCM0z5w87kL22CxfcH05ZpYlu+b4J7mw=
 github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
@@ -184,8 +184,8 @@ golang.org/x/crypto v0.13.0/go.mod h1:y6Z2r+Rw4iayiXXAIxJIDAJ1zMW4yaTpebo8fPOliY
 golang.org/x/crypto v0.19.0/go.mod h1:Iy9bg/ha4yyC70EfRS8jz+B6ybOBKMaSxLj6P6oBDfU=
 golang.org/x/crypto v0.23.0/go.mod h1:CKFgDieR+mRhux2Lsu27y0fO304Db0wZe70UKqHu0v8=
 golang.org/x/crypto v0.31.0/go.mod h1:kDsLvtWBEx7MV9tJOj9bnXsPbxwJQ6csT/x4KIN4Ssk=
-golang.org/x/crypto v0.46.0 h1:cKRW/pmt1pKAfetfu+RCEvjvZkA9RimPbh7bhFjGVBU=
-golang.org/x/crypto v0.46.0/go.mod h1:Evb/oLKmMraqjZ2iQTwDwvCtJkczlDuTmdJXoZVzqU0=
+golang.org/x/crypto v0.47.0 h1:V6e3FRj+n4dbpw86FJ8Fv7XVOql7TEwpHapKoMJ/GO8=
+golang.org/x/crypto v0.47.0/go.mod h1:ff3Y9VzzKbwSSEzWqJsJVBnWmRwRSHt/6Op5n9bQc4A=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/mod v0.12.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
@@ -200,8 +200,8 @@ golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/net v0.15.0/go.mod h1:idbUs1IY1+zTqbi8yxTbhexhEEk5ur9LInksu6HrEpk=
 golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
-golang.org/x/net v0.48.0 h1:zyQRTTrjc33Lhh0fBgT/H3oZq9WuvRR5gPC70xpDiQU=
-golang.org/x/net v0.48.0/go.mod h1:+ndRgGjkh8FGtu1w1FGbEC31if4VrNVMuKTgcAAnQRY=
+golang.org/x/net v0.49.0 h1:eeHFmOGUTtaaPSGNmjBKpbng9MulQsJURQUAfUwY++o=
+golang.org/x/net v0.49.0/go.mod h1:/ysNB2EvaqvesRkuLAyjI1ycPZlQHM3q01F02UY/MV8=
 golang.org/x/oauth2 v0.34.0 h1:hqK/t4AKgbqWkdkcAeI8XLmbK+4m4G5YeQRrmiotGlw=
 golang.org/x/oauth2 v0.34.0/go.mod h1:lzm5WQJQwKZ3nwavOZ3IS5Aulzxi68dUSgRHujetwEA=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -225,8 +225,8 @@ golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.28.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/sys v0.39.0 h1:CvCKL8MeisomCi6qNZ+wbb0DN9E5AATixKsvNtMoMFk=
-golang.org/x/sys v0.39.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/sys v0.40.0 h1:DBZZqJ2Rkml6QMQsZywtnjnnGvHza6BTfYFWY9kjEWQ=
+golang.org/x/sys v0.40.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 golang.org/x/telemetry v0.0.0-20240228155512-f48c80bd79b2/go.mod h1:TeRTkGYfJXctD9OcfyVLyj2J3IxLnKwHJR8f4D8a3YE=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
@@ -236,8 +236,8 @@ golang.org/x/term v0.12.0/go.mod h1:owVbMEjm3cBLCHdkQu9b1opXd4ETQWc3BhuQGKgXgvU=
 golang.org/x/term v0.17.0/go.mod h1:lLRBjIVuehSbZlaOtGMbcMncT+aqLLLmKrsjNrUguwk=
 golang.org/x/term v0.20.0/go.mod h1:8UkIAJTvZgivsXaD6/pH6U9ecQzZ45awqEOzuCvwpFY=
 golang.org/x/term v0.27.0/go.mod h1:iMsnZpn0cago0GOrHO2+Y7u7JPn5AylBrcoWkElMTSM=
-golang.org/x/term v0.38.0 h1:PQ5pkm/rLO6HnxFR7N2lJHOZX6Kez5Y1gDSJla6jo7Q=
-golang.org/x/term v0.38.0/go.mod h1:bSEAKrOT1W+VSu9TSCMtoGEOUcKxOKgl3LE5QEF/xVg=
+golang.org/x/term v0.39.0 h1:RclSuaJf32jOqZz74CkPA9qFuVTX7vhLlpfj/IGWlqY=
+golang.org/x/term v0.39.0/go.mod h1:yxzUCTP/U+FzoxfdKmLaA0RV1WgE0VY7hXBwKtY/4ww=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
@@ -249,8 +249,8 @@ golang.org/x/text v0.13.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/text v0.15.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
-golang.org/x/text v0.32.0 h1:ZD01bjUt1FQ9WJ0ClOL5vxgxOI/sVCNgX1YtKwcY0mU=
-golang.org/x/text v0.32.0/go.mod h1:o/rUWzghvpD5TXrTIBuJU77MTaN0ljMWE47kxGJQ7jY=
+golang.org/x/text v0.33.0 h1:B3njUFyqtHDUI5jMn1YIr5B0IE2U0qck04r6d4KPAxE=
+golang.org/x/text v0.33.0/go.mod h1:LuMebE6+rBincTi9+xWTY8TztLzKHc/9C1uBCG27+q8=
 golang.org/x/time v0.14.0 h1:MRx4UaLrDotUKUdCIqzPC48t1Y9hANFKIRpNx+Te8PI=
 golang.org/x/time v0.14.0/go.mod h1:eL/Oa2bBBK0TkX57Fyni+NgnyQQN4LitPmob2Hjnqw4=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
@@ -263,18 +263,18 @@ golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gonum.org/v1/gonum v0.16.0 h1:5+ul4Swaf3ESvrOnidPp4GZbzf0mxVQpDCYUQE7OJfk=
 gonum.org/v1/gonum v0.16.0/go.mod h1:fef3am4MQ93R2HHpKnLk4/Tbh/s0+wqD5nfa6Pnwy4E=
-google.golang.org/api v0.258.0 h1:IKo1j5FBlN74fe5isA2PVozN3Y5pwNKriEgAXPOkDAc=
-google.golang.org/api v0.258.0/go.mod h1:qhOMTQEZ6lUps63ZNq9jhODswwjkjYYguA7fA3TBFww=
+google.golang.org/api v0.259.0 h1:90TaGVIxScrh1Vn/XI2426kRpBqHwWIzVBzJsVZ5XrQ=
+google.golang.org/api v0.259.0/go.mod h1:LC2ISWGWbRoyQVpxGntWwLWN/vLNxxKBK9KuJRI8Te4=
 google.golang.org/appengine/v2 v2.0.6 h1:LvPZLGuchSBslPBp+LAhihBeGSiRh1myRoYK4NtuBIw=
 google.golang.org/appengine/v2 v2.0.6/go.mod h1:WoEXGoXNfa0mLvaH5sV3ZSGXwVmy8yf7Z1JKf3J3wLI=
-google.golang.org/genproto v0.0.0-20251213004720-97cd9d5aeac2 h1:stRtB2UVzFOWnorVuwF0BVVEjQ3AN6SjHWdg811UIQM=
-google.golang.org/genproto v0.0.0-20251213004720-97cd9d5aeac2/go.mod h1:yJ2HH4EHEDTd3JiLmhds6NkJ17ITVYOdV3m3VKOnws0=
-google.golang.org/genproto/googleapis/api v0.0.0-20251213004720-97cd9d5aeac2 h1:7LRqPCEdE4TP4/9psdaB7F2nhZFfBiGJomA5sojLWdU=
-google.golang.org/genproto/googleapis/api v0.0.0-20251213004720-97cd9d5aeac2/go.mod h1:+rXWjjaukWZun3mLfjmVnQi18E1AsFbDN9QdJ5YXLto=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20251213004720-97cd9d5aeac2 h1:2I6GHUeJ/4shcDpoUlLs/2WPnhg7yJwvXtqcMJt9liA=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20251213004720-97cd9d5aeac2/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
-google.golang.org/grpc v1.77.0 h1:wVVY6/8cGA6vvffn+wWK5ToddbgdU3d8MNENr4evgXM=
-google.golang.org/grpc v1.77.0/go.mod h1:z0BY1iVj0q8E1uSQCjL9cppRj+gnZjzDnzV0dHhrNig=
+google.golang.org/genproto v0.0.0-20260112192933-99fd39fd28a9 h1:wFALHMUiWKkK/x6rSxm79KpSnUyh7ks2E+mel670Dc4=
+google.golang.org/genproto v0.0.0-20260112192933-99fd39fd28a9/go.mod h1:wE6SUYr3iNtF/D0GxVAjT+0CbDFktQNssYs9PVptCt4=
+google.golang.org/genproto/googleapis/api v0.0.0-20260112192933-99fd39fd28a9 h1:4DKBrmaqeptdEzp21EfrOEh8LE7PJ5ywH6wydSbOfGY=
+google.golang.org/genproto/googleapis/api v0.0.0-20260112192933-99fd39fd28a9/go.mod h1:dd646eSK+Dk9kxVBl1nChEOhJPtMXriCcVb4x3o6J+E=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20260112192933-99fd39fd28a9 h1:IY6/YYRrFUk0JPp0xOVctvFIVuRnjccihY5kxf5g0TE=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20260112192933-99fd39fd28a9/go.mod h1:j9x/tPzZkyxcgEFkiKEEGxfvyumM01BEtsW8xzOahRQ=
+google.golang.org/grpc v1.78.0 h1:K1XZG/yGDJnzMdd/uZHAkVqJE+xIDOcmdSFZkBUicNc=
+google.golang.org/grpc v1.78.0/go.mod h1:I47qjTo4OKbMkjA/aOOwxDIiPSBofUtQUI5EfpWvW7U=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.30.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
 google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -99,6 +99,8 @@ nav:
      - "Known issues": known-issues.md
      - "Deprecation notices": deprecations.md
      - "Development": develop.md
+      - "Contributing": contributing.md
      - "Privacy policy": privacy.md
+      - "Contact": contact.md


--- a/server/errors.go
+++ b/server/errors.go
@@ -3,8 +3,9 @@ package server
 import (
 	"encoding/json"
 	"fmt"
-	"heckel.io/ntfy/v2/log"
 	"net/http"
+
+	"heckel.io/ntfy/v2/log"
 )

 // errHTTP is a generic HTTP error for any non-200 HTTP error
@@ -125,6 +126,7 @@ var (
 	errHTTPBadRequestInvalidUsername                 = &errHTTP{40046, http.StatusBadRequest, "invalid request: invalid username", "", nil}
 	errHTTPBadRequestTemplateFileNotFound            = &errHTTP{40047, http.StatusBadRequest, "invalid request: template file not found", "https://ntfy.sh/docs/publish/#message-templating", nil}
 	errHTTPBadRequestTemplateFileInvalid             = &errHTTP{40048, http.StatusBadRequest, "invalid request: template file invalid", "https://ntfy.sh/docs/publish/#message-templating", nil}
+	errHTTPBadRequestSequenceIDInvalid               = &errHTTP{40049, http.StatusBadRequest, "invalid request: sequence ID invalid", "https://ntfy.sh/docs/publish/#updating-deleting-notifications", nil}
 	errHTTPNotFound                                  = &errHTTP{40401, http.StatusNotFound, "page not found", "", nil}
 	errHTTPUnauthorized                              = &errHTTP{40101, http.StatusUnauthorized, "unauthorized", "https://ntfy.sh/docs/publish/#authentication", nil}
 	errHTTPForbidden                                 = &errHTTP{40301, http.StatusForbidden, "forbidden", "https://ntfy.sh/docs/publish/#authentication", nil}
--- a/server/message_cache.go
+++ b/server/message_cache.go
@@ -29,7 +29,9 @@ const (
 		CREATE TABLE IF NOT EXISTS messages (
 			id INTEGER PRIMARY KEY AUTOINCREMENT,
 			mid TEXT NOT NULL,
+			sequence_id TEXT NOT NULL,
 			time INT NOT NULL,
+			event TEXT NOT NULL,
 			expires INT NOT NULL,
 			topic TEXT NOT NULL,
 			message TEXT NOT NULL,
@@ -52,6 +54,7 @@ const (
 			published INT NOT NULL
 		);
 		CREATE INDEX IF NOT EXISTS idx_mid ON messages (mid);
+		CREATE INDEX IF NOT EXISTS idx_sequence_id ON messages (sequence_id);
 		CREATE INDEX IF NOT EXISTS idx_time ON messages (time);
 		CREATE INDEX IF NOT EXISTS idx_topic ON messages (topic);
 		CREATE INDEX IF NOT EXISTS idx_expires ON messages (expires);
@@ -66,50 +69,50 @@ const (
 		COMMIT;
 	`
 	insertMessageQuery = `
-		INSERT INTO messages (mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_deleted, sender, user, content_type, encoding, published)
-		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+		INSERT INTO messages (mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_deleted, sender, user, content_type, encoding, published)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
 	`
 	deleteMessageQuery                = `DELETE FROM messages WHERE mid = ?`
 	updateMessagesForTopicExpiryQuery = `UPDATE messages SET expires = ? WHERE topic = ?`
 	selectRowIDFromMessageID          = `SELECT id FROM messages WHERE mid = ?` // Do not include topic, see #336 and TestServer_PollSinceID_MultipleTopics
 	selectMessagesByIDQuery           = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
 		WHERE mid = ?
 	`
 	selectMessagesSinceTimeQuery = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
 		WHERE topic = ? AND time >= ? AND published = 1
 		ORDER BY time, id
 	`
 	selectMessagesSinceTimeIncludeScheduledQuery = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
 		WHERE topic = ? AND time >= ?
 		ORDER BY time, id
 	`
 	selectMessagesSinceIDQuery = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
-		WHERE topic = ? AND id > ? AND published = 1 
+		WHERE topic = ? AND id > ? AND published = 1
 		ORDER BY time, id
 	`
 	selectMessagesSinceIDIncludeScheduledQuery = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
 		WHERE topic = ? AND (id > ? OR published = 0)
 		ORDER BY time, id
 	`
 	selectMessagesLatestQuery = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
 		WHERE topic = ? AND published = 1
 		ORDER BY time DESC, id DESC
 		LIMIT 1
 	`
 	selectMessagesDueQuery = `
-		SELECT mid, time, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
+		SELECT mid, sequence_id, time, event, expires, topic, message, title, priority, tags, click, icon, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, user, content_type, encoding
 		FROM messages
 		WHERE time <= ? AND published = 0
 		ORDER BY time, id
@@ -131,7 +134,7 @@ const (

 // Schema management queries
 const (
-	currentSchemaVersion          = 13
+	currentSchemaVersion          = 14
 	createSchemaVersionTableQuery = `
 		CREATE TABLE IF NOT EXISTS schemaVersion (
 			id INT PRIMARY KEY,
@@ -260,6 +263,13 @@ const (
 	migrate12To13AlterMessagesTableQuery = `
 		CREATE INDEX IF NOT EXISTS idx_topic ON messages (topic);
 	`
+
+	//13 -> 14
+	migrate13To14AlterMessagesTableQuery = `
+		ALTER TABLE messages ADD COLUMN sequence_id TEXT NOT NULL DEFAULT('');
+		ALTER TABLE messages ADD COLUMN event TEXT NOT NULL DEFAULT('message');
+		CREATE INDEX IF NOT EXISTS idx_sequence_id ON messages (sequence_id);
+	`
 )

 var (
@@ -277,6 +287,7 @@ var (
 		10: migrateFrom10,
 		11: migrateFrom11,
 		12: migrateFrom12,
+		13: migrateFrom13,
 	}
 )

@@ -369,7 +380,7 @@ func (c *messageCache) addMessages(ms []*message) error {
 	}
 	defer stmt.Close()
 	for _, m := range ms {
-		if m.Event != messageEvent {
+		if m.Event != messageEvent && m.Event != messageDeleteEvent && m.Event != messageClearEvent {
 			return errUnexpectedMessageType
 		}
 		published := m.Time <= time.Now().Unix()
@@ -397,7 +408,9 @@ func (c *messageCache) addMessages(ms []*message) error {
 		}
 		_, err := stmt.Exec(
 			m.ID,
+			m.SequenceID,
 			m.Time,
+			m.Event,
 			m.Expires,
 			m.Topic,
 			m.Message,
@@ -706,10 +719,12 @@ func readMessages(rows *sql.Rows) ([]*message, error) {
 func readMessage(rows *sql.Rows) (*message, error) {
 	var timestamp, expires, attachmentSize, attachmentExpires int64
 	var priority int
-	var id, topic, msg, title, tagsStr, click, icon, actionsStr, attachmentName, attachmentType, attachmentURL, sender, user, contentType, encoding string
+	var id, sequenceID, event, topic, msg, title, tagsStr, click, icon, actionsStr, attachmentName, attachmentType, attachmentURL, sender, user, contentType, encoding string
 	err := rows.Scan(
 		&id,
+		&sequenceID,
 		&timestamp,
+		&event,
 		&expires,
 		&topic,
 		&msg,
@@ -758,9 +773,10 @@ func readMessage(rows *sql.Rows) (*message, error) {
 	}
 	return &message{
 		ID:          id,
+		SequenceID:  sequenceID,
 		Time:        timestamp,
 		Expires:     expires,
-		Event:       messageEvent,
+		Event:       event,
 		Topic:       topic,
 		Message:     msg,
 		Title:       title,
@@ -1030,3 +1046,19 @@ func migrateFrom12(db *sql.DB, _ time.Duration) error {
 	}
 	return tx.Commit()
 }
+
+func migrateFrom13(db *sql.DB, _ time.Duration) error {
+	log.Tag(tagMessageCache).Info("Migrating cache database schema: from 13 to 14")
+	tx, err := db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+	if _, err := tx.Exec(migrate13To14AlterMessagesTableQuery); err != nil {
+		return err
+	}
+	if _, err := tx.Exec(updateSchemaVersion, 14); err != nil {
+		return err
+	}
+	return tx.Commit()
+}
--- a/server/message_cache_test.go
+++ b/server/message_cache_test.go
@@ -319,6 +319,7 @@ func testCacheAttachments(t *testing.T, c *messageCache) {
 	expires1 := time.Now().Add(-4 * time.Hour).Unix() // Expired
 	m := newDefaultMessage("mytopic", "flower for you")
 	m.ID = "m1"
+	m.SequenceID = "m1"
 	m.Sender = netip.MustParseAddr("1.2.3.4")
 	m.Attachment = &attachment{
 		Name:    "flower.jpg",
@@ -332,6 +333,7 @@ func testCacheAttachments(t *testing.T, c *messageCache) {
 	expires2 := time.Now().Add(2 * time.Hour).Unix() // Future
 	m = newDefaultMessage("mytopic", "sending you a car")
 	m.ID = "m2"
+	m.SequenceID = "m2"
 	m.Sender = netip.MustParseAddr("1.2.3.4")
 	m.Attachment = &attachment{
 		Name:    "car.jpg",
@@ -345,6 +347,7 @@ func testCacheAttachments(t *testing.T, c *messageCache) {
 	expires3 := time.Now().Add(1 * time.Hour).Unix() // Future
 	m = newDefaultMessage("another-topic", "sending you another car")
 	m.ID = "m3"
+	m.SequenceID = "m3"
 	m.User = "u_BAsbaAa"
 	m.Sender = netip.MustParseAddr("5.6.7.8")
 	m.Attachment = &attachment{
@@ -400,11 +403,13 @@ func TestMemCache_Attachments_Expired(t *testing.T) {
 func testCacheAttachmentsExpired(t *testing.T, c *messageCache) {
 	m := newDefaultMessage("mytopic", "flower for you")
 	m.ID = "m1"
+	m.SequenceID = "m1"
 	m.Expires = time.Now().Add(time.Hour).Unix()
 	require.Nil(t, c.AddMessage(m))

 	m = newDefaultMessage("mytopic", "message with attachment")
 	m.ID = "m2"
+	m.SequenceID = "m2"
 	m.Expires = time.Now().Add(2 * time.Hour).Unix()
 	m.Attachment = &attachment{
 		Name:    "car.jpg",
@@ -417,6 +422,7 @@ func testCacheAttachmentsExpired(t *testing.T, c *messageCache) {

 	m = newDefaultMessage("mytopic", "message with external attachment")
 	m.ID = "m3"
+	m.SequenceID = "m3"
 	m.Expires = time.Now().Add(2 * time.Hour).Unix()
 	m.Attachment = &attachment{
 		Name:    "car.jpg",
@@ -428,6 +434,7 @@ func testCacheAttachmentsExpired(t *testing.T, c *messageCache) {

 	m = newDefaultMessage("mytopic2", "message with expired attachment")
 	m.ID = "m4"
+	m.SequenceID = "m4"
 	m.Expires = time.Now().Add(2 * time.Hour).Unix()
 	m.Attachment = &attachment{
 		Name:    "expired-car.jpg",
--- a/server/server.go
+++ b/server/server.go
@@ -80,11 +80,12 @@ var (
 	wsPathRegex            = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/ws$`)
 	authPathRegex          = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}(,[-_A-Za-z0-9]{1,64})*/auth$`)
 	publishPathRegex       = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}/(publish|send|trigger)$`)
+	updatePathRegex        = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}/[-_A-Za-z0-9]{1,64}$`)
+	clearPathRegex         = regexp.MustCompile(`^/[-_A-Za-z0-9]{1,64}/[-_A-Za-z0-9]{1,64}/(read|clear)$`)
+	sequenceIDRegex        = topicRegex

 	webConfigPath                                        = "/config.js"
 	webManifestPath                                      = "/manifest.webmanifest"
-	webRootHTMLPath                                      = "/app.html"
-	webServiceWorkerPath                                 = "/sw.js"
 	accountPath                                          = "/account"
 	matrixPushPath                                       = "/_matrix/push/v1/notify"
 	metricsPath                                          = "/metrics"
@@ -108,7 +109,7 @@ var (
 	apiAccountBillingSubscriptionCheckoutSuccessTemplate = "/v1/account/billing/subscription/success/{CHECKOUT_SESSION_ID}"
 	apiAccountBillingSubscriptionCheckoutSuccessRegex    = regexp.MustCompile(`/v1/account/billing/subscription/success/(.+)$`)
 	apiAccountReservationSingleRegex                     = regexp.MustCompile(`/v1/account/reservation/([-_A-Za-z0-9]{1,64})$`)
-	staticRegex                                          = regexp.MustCompile(`^/static/.+`)
+	staticRegex                                          = regexp.MustCompile(`^/(static/.+|app.html|sw.js|sw.js.map)$`)
 	docsRegex                                            = regexp.MustCompile(`^/docs(|/.*)$`)
 	fileRegex                                            = regexp.MustCompile(`^/file/([-_A-Za-z0-9]{1,64})(?:\.[A-Za-z0-9]{1,16})?$`)
 	urlRegex                                             = regexp.MustCompile(`^https?://`)
@@ -137,7 +138,7 @@ var (
 const (
 	firebaseControlTopic     = "~control"                // See Android if changed
 	firebasePollTopic        = "~poll"                   // See iOS if changed (DISABLED for now)
-	emptyMessageBody         = "triggered"               // Used if message body is empty
+	emptyMessageBody         = "triggered"               // Used when a message body is empty
 	newMessageBody           = "New message"             // Used in poll requests as generic message
 	defaultAttachmentMessage = "You received a file: %s" // Used if message body is empty, and there is an attachment
 	encodingBase64           = "base64"                  // Used mainly for binary UnifiedPush messages
@@ -531,7 +532,7 @@ func (s *Server) handleInternal(w http.ResponseWriter, r *http.Request, v *visit
 		return s.handleMatrixDiscovery(w)
 	} else if r.Method == http.MethodGet && r.URL.Path == metricsPath && s.metricsHandler != nil {
 		return s.handleMetrics(w, r, v)
-	} else if r.Method == http.MethodGet && (staticRegex.MatchString(r.URL.Path) || r.URL.Path == webServiceWorkerPath || r.URL.Path == webRootHTMLPath) {
+	} else if r.Method == http.MethodGet && staticRegex.MatchString(r.URL.Path) {
 		return s.ensureWebEnabled(s.handleStatic)(w, r, v)
 	} else if r.Method == http.MethodGet && docsRegex.MatchString(r.URL.Path) {
 		return s.ensureWebEnabled(s.handleDocs)(w, r, v)
@@ -543,8 +544,12 @@ func (s *Server) handleInternal(w http.ResponseWriter, r *http.Request, v *visit
 		return s.transformBodyJSON(s.limitRequestsWithTopic(s.authorizeTopicWrite(s.handlePublish)))(w, r, v)
 	} else if r.Method == http.MethodPost && r.URL.Path == matrixPushPath {
 		return s.transformMatrixJSON(s.limitRequestsWithTopic(s.authorizeTopicWrite(s.handlePublishMatrix)))(w, r, v)
-	} else if (r.Method == http.MethodPut || r.Method == http.MethodPost) && topicPathRegex.MatchString(r.URL.Path) {
+	} else if (r.Method == http.MethodPut || r.Method == http.MethodPost) && (topicPathRegex.MatchString(r.URL.Path) || updatePathRegex.MatchString(r.URL.Path)) {
 		return s.limitRequestsWithTopic(s.authorizeTopicWrite(s.handlePublish))(w, r, v)
+	} else if r.Method == http.MethodDelete && updatePathRegex.MatchString(r.URL.Path) {
+		return s.limitRequestsWithTopic(s.authorizeTopicWrite(s.handleDelete))(w, r, v)
+	} else if r.Method == http.MethodPut && clearPathRegex.MatchString(r.URL.Path) {
+		return s.limitRequestsWithTopic(s.authorizeTopicWrite(s.handleClear))(w, r, v)
 	} else if r.Method == http.MethodGet && publishPathRegex.MatchString(r.URL.Path) {
 		return s.limitRequestsWithTopic(s.authorizeTopicWrite(s.handlePublish))(w, r, v)
 	} else if r.Method == http.MethodGet && jsonPathRegex.MatchString(r.URL.Path) {
@@ -872,7 +877,7 @@ func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, v *visito
 		return err
 	}
 	minc(metricMessagesPublishedSuccess)
-	return s.writeJSON(w, m)
+	return s.writeJSON(w, m.forJSON())
 }

 func (s *Server) handlePublishMatrix(w http.ResponseWriter, r *http.Request, v *visitor) error {
@@ -900,6 +905,58 @@ func (s *Server) handlePublishMatrix(w http.ResponseWriter, r *http.Request, v *
 	return writeMatrixSuccess(w)
 }

+func (s *Server) handleDelete(w http.ResponseWriter, r *http.Request, v *visitor) error {
+	return s.handleActionMessage(w, r, v, messageDeleteEvent)
+}
+
+func (s *Server) handleClear(w http.ResponseWriter, r *http.Request, v *visitor) error {
+	return s.handleActionMessage(w, r, v, messageClearEvent)
+}
+
+func (s *Server) handleActionMessage(w http.ResponseWriter, r *http.Request, v *visitor, event string) error {
+	t, err := fromContext[*topic](r, contextTopic)
+	if err != nil {
+		return err
+	}
+	vrate, err := fromContext[*visitor](r, contextRateVisitor)
+	if err != nil {
+		return err
+	}
+	if !util.ContainsIP(s.config.VisitorRequestExemptPrefixes, v.ip) && !vrate.MessageAllowed() {
+		return errHTTPTooManyRequestsLimitMessages.With(t)
+	}
+	sequenceID, e := s.sequenceIDFromPath(r.URL.Path)
+	if e != nil {
+		return e.With(t)
+	}
+	// Create an action message with the given event type
+	m := newActionMessage(event, t.ID, sequenceID)
+	m.Sender = v.IP()
+	m.User = v.MaybeUserID()
+	m.Expires = time.Unix(m.Time, 0).Add(v.Limits().MessageExpiryDuration).Unix()
+	// Publish to subscribers
+	if err := t.Publish(v, m); err != nil {
+		return err
+	}
+	// Send to Firebase for Android clients
+	if s.firebaseClient != nil {
+		go s.sendToFirebase(v, m)
+	}
+	// Send to web push endpoints
+	if s.config.WebPushPublicKey != "" {
+		go s.publishToWebPushEndpoints(v, m)
+	}
+	// Add to message cache
+	if err := s.messageCache.AddMessage(m); err != nil {
+		return err
+	}
+	logvrm(v, r, m).Tag(tagPublish).Debug("Published %s for sequence ID %s", event, sequenceID)
+	s.mu.Lock()
+	s.messages++
+	s.mu.Unlock()
+	return s.writeJSON(w, m.forJSON())
+}
+
 func (s *Server) sendToFirebase(v *visitor, m *message) {
 	logvm(v, m).Tag(tagFirebase).Debug("Publishing to Firebase")
 	if err := s.firebaseClient.Send(v, m); err != nil {
@@ -957,6 +1014,24 @@ func (s *Server) forwardPollRequest(v *visitor, m *message) {
 }

 func (s *Server) parsePublishParams(r *http.Request, m *message) (cache bool, firebase bool, email, call string, template templateMode, unifiedpush bool, err *errHTTP) {
+	if r.Method != http.MethodGet && updatePathRegex.MatchString(r.URL.Path) {
+		pathSequenceID, err := s.sequenceIDFromPath(r.URL.Path)
+		if err != nil {
+			return false, false, "", "", "", false, err
+		}
+		m.SequenceID = pathSequenceID
+	} else {
+		sequenceID := readParam(r, "x-sequence-id", "sequence-id", "sid")
+		if sequenceID != "" {
+			if sequenceIDRegex.MatchString(sequenceID) {
+				m.SequenceID = sequenceID
+			} else {
+				return false, false, "", "", "", false, errHTTPBadRequestSequenceIDInvalid
+			}
+		} else {
+			m.SequenceID = m.ID
+		}
+	}
 	cache = readBoolParam(r, true, "x-cache", "cache")
 	firebase = readBoolParam(r, true, "x-firebase", "firebase")
 	m.Title = readParam(r, "x-title", "title", "t")
@@ -1271,7 +1346,7 @@ func (s *Server) handleBodyAsAttachment(r *http.Request, v *visitor, m *message,
 func (s *Server) handleSubscribeJSON(w http.ResponseWriter, r *http.Request, v *visitor) error {
 	encoder := func(msg *message) (string, error) {
 		var buf bytes.Buffer
-		if err := json.NewEncoder(&buf).Encode(&msg); err != nil {
+		if err := json.NewEncoder(&buf).Encode(msg.forJSON()); err != nil {
 			return "", err
 		}
 		return buf.String(), nil
@@ -1282,10 +1357,10 @@ func (s *Server) handleSubscribeJSON(w http.ResponseWriter, r *http.Request, v *
 func (s *Server) handleSubscribeSSE(w http.ResponseWriter, r *http.Request, v *visitor) error {
 	encoder := func(msg *message) (string, error) {
 		var buf bytes.Buffer
-		if err := json.NewEncoder(&buf).Encode(&msg); err != nil {
+		if err := json.NewEncoder(&buf).Encode(msg.forJSON()); err != nil {
 			return "", err
 		}
-		if msg.Event != messageEvent {
+		if msg.Event != messageEvent && msg.Event != messageDeleteEvent && msg.Event != messageClearEvent {
 			return fmt.Sprintf("event: %s\ndata: %s\n", msg.Event, buf.String()), nil // Browser's .onmessage() does not fire on this!
 		}
 		return fmt.Sprintf("data: %s\n", buf.String()), nil
@@ -1695,6 +1770,15 @@ func (s *Server) topicsFromPath(path string) ([]*topic, string, error) {
 	return topics, parts[1], nil
 }

+// sequenceIDFromPath returns the sequence ID from a path like /mytopic/sequenceIdHere
+func (s *Server) sequenceIDFromPath(path string) (string, *errHTTP) {
+	parts := strings.Split(path, "/")
+	if len(parts) < 3 {
+		return "", errHTTPBadRequestSequenceIDInvalid
+	}
+	return parts[2], nil
+}
+
 // topicsFromIDs returns the topics with the given IDs, creating them if they don't exist.
 func (s *Server) topicsFromIDs(ids ...string) ([]*topic, error) {
 	s.mu.Lock()
@@ -1949,6 +2033,9 @@ func (s *Server) transformBodyJSON(next handleFunc) handleFunc {
 		if m.Firebase != "" {
 			r.Header.Set("X-Firebase", m.Firebase)
 		}
+		if m.SequenceID != "" {
+			r.Header.Set("X-Sequence-ID", m.SequenceID)
+		}
 		return next(w, r, v)
 	}
 }
--- a/server/server_firebase.go
+++ b/server/server_firebase.go
@@ -143,6 +143,15 @@ func toFirebaseMessage(m *message, auther user.Auther) (*messaging.Message, erro
 			"poll_id": m.PollID,
 		}
 		apnsConfig = createAPNSAlertConfig(m, data)
+	case messageDeleteEvent, messageClearEvent:
+		data = map[string]string{
+			"id":          m.ID,
+			"time":        fmt.Sprintf("%d", m.Time),
+			"event":       m.Event,
+			"topic":       m.Topic,
+			"sequence_id": m.SequenceID,
+		}
+		apnsConfig = createAPNSBackgroundConfig(data)
 	case messageEvent:
 		if auther != nil {
 			// If "anonymous read" for a topic is not allowed, we cannot send the message along
@@ -161,6 +170,7 @@ func toFirebaseMessage(m *message, auther user.Auther) (*messaging.Message, erro
 			"time":         fmt.Sprintf("%d", m.Time),
 			"event":        m.Event,
 			"topic":        m.Topic,
+			"sequence_id":  m.SequenceID,
 			"priority":     fmt.Sprintf("%d", m.Priority),
 			"tags":         strings.Join(m.Tags, ","),
 			"click":        m.Click,
--- a/server/server_firebase_test.go
+++ b/server/server_firebase_test.go
@@ -177,6 +177,7 @@ func TestToFirebaseMessage_Message_Normal_Allowed(t *testing.T) {
 				"time":               fmt.Sprintf("%d", m.Time),
 				"event":              "message",
 				"topic":              "mytopic",
+				"sequence_id":        "",
 				"priority":           "4",
 				"tags":               strings.Join(m.Tags, ","),
 				"click":              "https://google.com",
@@ -199,6 +200,7 @@ func TestToFirebaseMessage_Message_Normal_Allowed(t *testing.T) {
 		"time":               fmt.Sprintf("%d", m.Time),
 		"event":              "message",
 		"topic":              "mytopic",
+		"sequence_id":        "",
 		"priority":           "4",
 		"tags":               strings.Join(m.Tags, ","),
 		"click":              "https://google.com",
@@ -232,6 +234,7 @@ func TestToFirebaseMessage_Message_Normal_Not_Allowed(t *testing.T) {
 		"time":         fmt.Sprintf("%d", m.Time),
 		"event":        "poll_request",
 		"topic":        "mytopic",
+		"sequence_id":  "",
 		"message":      "New message",
 		"title":        "",
 		"tags":         "",
--- a/server/server_test.go
+++ b/server/server_test.go
@@ -8,8 +8,6 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
-	"golang.org/x/crypto/bcrypt"
-	"heckel.io/ntfy/v2/user"
 	"io"
 	"net/http"
 	"net/http/httptest"
@@ -24,7 +22,9 @@ import (
 	"time"

 	"github.com/stretchr/testify/require"
+	"golang.org/x/crypto/bcrypt"
 	"heckel.io/ntfy/v2/log"
+	"heckel.io/ntfy/v2/user"
 	"heckel.io/ntfy/v2/util"
 )

@@ -678,6 +678,86 @@ func TestServer_PublishInvalidTopic(t *testing.T) {
 	require.Equal(t, 40010, toHTTPError(t, response.Body.String()).Code)
 }

+func TestServer_PublishWithSIDInPath(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "POST", "/mytopic/sid", "message", nil)
+	msg := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg.ID)
+	require.Equal(t, "sid", msg.SequenceID)
+}
+
+func TestServer_PublishWithSIDInHeader(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "POST", "/mytopic", "message", map[string]string{
+		"sid": "sid",
+	})
+	msg := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg.ID)
+	require.Equal(t, "sid", msg.SequenceID)
+}
+
+func TestServer_PublishWithSIDInPathAndHeader(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "PUT", "/mytopic/sid1", "message", map[string]string{
+		"sid": "sid2",
+	})
+	msg := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg.ID)
+	require.Equal(t, "sid1", msg.SequenceID) // Sequence ID in path has priority over header
+}
+
+func TestServer_PublishWithSIDInQuery(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "PUT", "/mytopic?sid=sid1", "message", nil)
+	msg := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg.ID)
+	require.Equal(t, "sid1", msg.SequenceID)
+}
+
+func TestServer_PublishWithSIDViaGet(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "GET", "/mytopic/publish?sid=sid1", "message", nil)
+	msg := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg.ID)
+	require.Equal(t, "sid1", msg.SequenceID)
+}
+
+func TestServer_PublishAsJSON_WithSequenceID(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	body := `{"topic":"mytopic","message":"A message","sequence_id":"my-sequence-123"}`
+	response := request(t, s, "PUT", "/", body, nil)
+	require.Equal(t, 200, response.Code)
+
+	msg := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg.ID)
+	require.Equal(t, "my-sequence-123", msg.SequenceID)
+}
+
+func TestServer_PublishWithInvalidSIDInPath(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "POST", "/mytopic/.", "message", nil)
+
+	require.Equal(t, 404, response.Code)
+}
+
+func TestServer_PublishWithInvalidSIDInHeader(t *testing.T) {
+	s := newTestServer(t, newTestConfig(t))
+
+	response := request(t, s, "POST", "/mytopic", "message", map[string]string{
+		"X-Sequence-ID": "*&?",
+	})
+
+	require.Equal(t, 400, response.Code)
+	require.Equal(t, 40049, toHTTPError(t, response.Body.String()).Code)
+}
+
 func TestServer_PollWithQueryFilters(t *testing.T) {
 	s := newTestServer(t, newTestConfig(t))

@@ -3209,6 +3289,212 @@ func TestServer_MessageTemplate_Until100_000(t *testing.T) {
 	require.Contains(t, toHTTPError(t, response.Body.String()).Message, "too many iterations")
 }

+func TestServer_DeleteMessage(t *testing.T) {
+	t.Parallel()
+	s := newTestServer(t, newTestConfig(t))
+
+	// Publish a message with a sequence ID
+	response := request(t, s, "PUT", "/mytopic/seq123", "original message", nil)
+	require.Equal(t, 200, response.Code)
+	msg := toMessage(t, response.Body.String())
+	require.Equal(t, "seq123", msg.SequenceID)
+	require.Equal(t, "message", msg.Event)
+
+	// Delete the message using DELETE method
+	response = request(t, s, "DELETE", "/mytopic/seq123", "", nil)
+	require.Equal(t, 200, response.Code)
+	deleteMsg := toMessage(t, response.Body.String())
+	require.Equal(t, "seq123", deleteMsg.SequenceID)
+	require.Equal(t, "message_delete", deleteMsg.Event)
+
+	// Poll and verify both messages are returned
+	response = request(t, s, "GET", "/mytopic/json?poll=1", "", nil)
+	require.Equal(t, 200, response.Code)
+	lines := strings.Split(strings.TrimSpace(response.Body.String()), "\n")
+	require.Equal(t, 2, len(lines))
+
+	msg1 := toMessage(t, lines[0])
+	msg2 := toMessage(t, lines[1])
+	require.Equal(t, "message", msg1.Event)
+	require.Equal(t, "message_delete", msg2.Event)
+	require.Equal(t, "seq123", msg1.SequenceID)
+	require.Equal(t, "seq123", msg2.SequenceID)
+}
+
+func TestServer_ClearMessage(t *testing.T) {
+	t.Parallel()
+	s := newTestServer(t, newTestConfig(t))
+
+	// Publish a message with a sequence ID
+	response := request(t, s, "PUT", "/mytopic/seq456", "original message", nil)
+	require.Equal(t, 200, response.Code)
+	msg := toMessage(t, response.Body.String())
+	require.Equal(t, "seq456", msg.SequenceID)
+	require.Equal(t, "message", msg.Event)
+
+	// Clear the message using PUT /topic/seq/clear
+	response = request(t, s, "PUT", "/mytopic/seq456/clear", "", nil)
+	require.Equal(t, 200, response.Code)
+	clearMsg := toMessage(t, response.Body.String())
+	require.Equal(t, "seq456", clearMsg.SequenceID)
+	require.Equal(t, "message_clear", clearMsg.Event)
+
+	// Poll and verify both messages are returned
+	response = request(t, s, "GET", "/mytopic/json?poll=1", "", nil)
+	require.Equal(t, 200, response.Code)
+	lines := strings.Split(strings.TrimSpace(response.Body.String()), "\n")
+	require.Equal(t, 2, len(lines))
+
+	msg1 := toMessage(t, lines[0])
+	msg2 := toMessage(t, lines[1])
+	require.Equal(t, "message", msg1.Event)
+	require.Equal(t, "message_clear", msg2.Event)
+	require.Equal(t, "seq456", msg1.SequenceID)
+	require.Equal(t, "seq456", msg2.SequenceID)
+}
+
+func TestServer_ClearMessage_ReadEndpoint(t *testing.T) {
+	// Test that /topic/seq/read also works
+	t.Parallel()
+	s := newTestServer(t, newTestConfig(t))
+
+	// Publish a message
+	response := request(t, s, "PUT", "/mytopic/seq789", "original message", nil)
+	require.Equal(t, 200, response.Code)
+
+	// Clear using /read endpoint
+	response = request(t, s, "PUT", "/mytopic/seq789/read", "", nil)
+	require.Equal(t, 200, response.Code)
+	clearMsg := toMessage(t, response.Body.String())
+	require.Equal(t, "seq789", clearMsg.SequenceID)
+	require.Equal(t, "message_clear", clearMsg.Event)
+}
+
+func TestServer_UpdateMessage(t *testing.T) {
+	t.Parallel()
+	s := newTestServer(t, newTestConfig(t))
+
+	// Publish original message
+	response := request(t, s, "PUT", "/mytopic/update-seq", "original message", nil)
+	require.Equal(t, 200, response.Code)
+	msg1 := toMessage(t, response.Body.String())
+	require.Equal(t, "update-seq", msg1.SequenceID)
+	require.Equal(t, "original message", msg1.Message)
+
+	// Update the message (same sequence ID, new content)
+	response = request(t, s, "PUT", "/mytopic/update-seq", "updated message", nil)
+	require.Equal(t, 200, response.Code)
+	msg2 := toMessage(t, response.Body.String())
+	require.Equal(t, "update-seq", msg2.SequenceID)
+	require.Equal(t, "updated message", msg2.Message)
+	require.NotEqual(t, msg1.ID, msg2.ID) // Different message IDs
+
+	// Poll and verify both versions are returned
+	response = request(t, s, "GET", "/mytopic/json?poll=1", "", nil)
+	require.Equal(t, 200, response.Code)
+	lines := strings.Split(strings.TrimSpace(response.Body.String()), "\n")
+	require.Equal(t, 2, len(lines))
+
+	polledMsg1 := toMessage(t, lines[0])
+	polledMsg2 := toMessage(t, lines[1])
+	require.Equal(t, "original message", polledMsg1.Message)
+	require.Equal(t, "updated message", polledMsg2.Message)
+	require.Equal(t, "update-seq", polledMsg1.SequenceID)
+	require.Equal(t, "update-seq", polledMsg2.SequenceID)
+}
+
+func TestServer_UpdateMessage_UsingMessageID(t *testing.T) {
+	t.Parallel()
+	s := newTestServer(t, newTestConfig(t))
+
+	// Publish original message without a sequence ID
+	response := request(t, s, "PUT", "/mytopic", "original message", nil)
+	require.Equal(t, 200, response.Code)
+	msg1 := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg1.ID)
+	require.Empty(t, msg1.SequenceID) // No sequence ID provided
+	require.Equal(t, "original message", msg1.Message)
+
+	// Update the message using the message ID as the sequence ID
+	response = request(t, s, "PUT", "/mytopic/"+msg1.ID, "updated message", nil)
+	require.Equal(t, 200, response.Code)
+	msg2 := toMessage(t, response.Body.String())
+	require.Equal(t, msg1.ID, msg2.SequenceID) // Message ID is now used as sequence ID
+	require.Equal(t, "updated message", msg2.Message)
+	require.NotEqual(t, msg1.ID, msg2.ID) // Different message IDs
+
+	// Poll and verify both versions are returned
+	response = request(t, s, "GET", "/mytopic/json?poll=1", "", nil)
+	require.Equal(t, 200, response.Code)
+	lines := strings.Split(strings.TrimSpace(response.Body.String()), "\n")
+	require.Equal(t, 2, len(lines))
+
+	polledMsg1 := toMessage(t, lines[0])
+	polledMsg2 := toMessage(t, lines[1])
+	require.Equal(t, "original message", polledMsg1.Message)
+	require.Equal(t, "updated message", polledMsg2.Message)
+	require.Empty(t, polledMsg1.SequenceID)          // Original has no sequence ID
+	require.Equal(t, msg1.ID, polledMsg2.SequenceID) // Update uses original message ID as sequence ID
+}
+
+func TestServer_DeleteAndClear_InvalidSequenceID(t *testing.T) {
+	t.Parallel()
+	s := newTestServer(t, newTestConfig(t))
+
+	// Test invalid sequence ID for delete (returns 404 because route doesn't match)
+	response := request(t, s, "DELETE", "/mytopic/invalid*seq", "", nil)
+	require.Equal(t, 404, response.Code)
+
+	// Test invalid sequence ID for clear (returns 404 because route doesn't match)
+	response = request(t, s, "PUT", "/mytopic/invalid*seq/clear", "", nil)
+	require.Equal(t, 404, response.Code)
+}
+
+func TestServer_DeleteMessage_WithFirebase(t *testing.T) {
+	sender := newTestFirebaseSender(10)
+	s := newTestServer(t, newTestConfig(t))
+	s.firebaseClient = newFirebaseClient(sender, &testAuther{Allow: true})
+
+	// Publish a message
+	response := request(t, s, "PUT", "/mytopic/firebase-seq", "test message", nil)
+	require.Equal(t, 200, response.Code)
+
+	time.Sleep(100 * time.Millisecond) // Firebase publishing happens
+	require.Equal(t, 1, len(sender.Messages()))
+	require.Equal(t, "message", sender.Messages()[0].Data["event"])
+
+	// Delete the message
+	response = request(t, s, "DELETE", "/mytopic/firebase-seq", "", nil)
+	require.Equal(t, 200, response.Code)
+
+	time.Sleep(100 * time.Millisecond) // Firebase publishing happens
+	require.Equal(t, 2, len(sender.Messages()))
+	require.Equal(t, "message_delete", sender.Messages()[1].Data["event"])
+	require.Equal(t, "firebase-seq", sender.Messages()[1].Data["sequence_id"])
+}
+
+func TestServer_ClearMessage_WithFirebase(t *testing.T) {
+	sender := newTestFirebaseSender(10)
+	s := newTestServer(t, newTestConfig(t))
+	s.firebaseClient = newFirebaseClient(sender, &testAuther{Allow: true})
+
+	// Publish a message
+	response := request(t, s, "PUT", "/mytopic/firebase-clear-seq", "test message", nil)
+	require.Equal(t, 200, response.Code)
+
+	time.Sleep(100 * time.Millisecond)
+	require.Equal(t, 1, len(sender.Messages()))
+
+	// Clear the message
+	response = request(t, s, "PUT", "/mytopic/firebase-clear-seq/clear", "", nil)
+	require.Equal(t, 200, response.Code)
+
+	time.Sleep(100 * time.Millisecond)
+	require.Equal(t, 2, len(sender.Messages()))
+	require.Equal(t, "message_clear", sender.Messages()[1].Data["event"])
+	require.Equal(t, "firebase-clear-seq", sender.Messages()[1].Data["sequence_id"])
+}
+
 func newTestConfig(t *testing.T) *Config {
 	conf := NewConfig()
 	conf.BaseURL = "http://127.0.0.1:12345"
--- a/server/server_webpush.go
+++ b/server/server_webpush.go
@@ -89,7 +89,7 @@ func (s *Server) publishToWebPushEndpoints(v *visitor, m *message) {
 		return
 	}
 	log.Tag(tagWebPush).With(v, m).Debug("Publishing web push message to %d subscribers", len(subscriptions))
-	payload, err := json.Marshal(newWebPushPayload(fmt.Sprintf("%s/%s", s.config.BaseURL, m.Topic), m))
+	payload, err := json.Marshal(newWebPushPayload(fmt.Sprintf("%s/%s", s.config.BaseURL, m.Topic), m.forJSON()))
 	if err != nil {
 		log.Tag(tagWebPush).Err(err).With(v, m).Warn("Unable to marshal expiring payload")
 		return
--- a/server/types.go
+++ b/server/types.go
@@ -12,10 +12,12 @@ import (

 // List of possible events
 const (
-	openEvent        = "open"
-	keepaliveEvent   = "keepalive"
-	messageEvent     = "message"
-	pollRequestEvent = "poll_request"
+	openEvent          = "open"
+	keepaliveEvent     = "keepalive"
+	messageEvent       = "message"
+	messageDeleteEvent = "message_delete"
+	messageClearEvent  = "message_clear"
+	pollRequestEvent   = "poll_request"
 )

 const (
@@ -24,10 +26,11 @@ const (

 // message represents a message published to a topic
 type message struct {
-	ID          string      `json:"id"`                // Random message ID
-	Time        int64       `json:"time"`              // Unix time in seconds
-	Expires     int64       `json:"expires,omitempty"` // Unix time in seconds (not required for open/keepalive)
-	Event       string      `json:"event"`             // One of the above
+	ID          string      `json:"id"`                    // Random message ID
+	SequenceID  string      `json:"sequence_id,omitempty"` // Message sequence ID for updating message contents (omitted if same as ID)
+	Time        int64       `json:"time"`                  // Unix time in seconds
+	Expires     int64       `json:"expires,omitempty"`     // Unix time in seconds (not required for open/keepalive)
+	Event       string      `json:"event"`                 // One of the above
 	Topic       string      `json:"topic"`
 	Title       string      `json:"title,omitempty"`
 	Message     string      `json:"message,omitempty"`
@@ -39,18 +42,19 @@ type message struct {
 	Attachment  *attachment `json:"attachment,omitempty"`
 	PollID      string      `json:"poll_id,omitempty"`
 	ContentType string      `json:"content_type,omitempty"` // text/plain by default (if empty), or text/markdown
-	Encoding    string      `json:"encoding,omitempty"`     // empty for raw UTF-8, or "base64" for encoded bytes
+	Encoding    string      `json:"encoding,omitempty"`     // Empty for raw UTF-8, or "base64" for encoded bytes
 	Sender      netip.Addr  `json:"-"`                      // IP address of uploader, used for rate limiting
 	User        string      `json:"-"`                      // UserID of the uploader, used to associated attachments
 }

 func (m *message) Context() log.Context {
 	fields := map[string]any{
-		"topic":             m.Topic,
-		"message_id":        m.ID,
-		"message_time":      m.Time,
-		"message_event":     m.Event,
-		"message_body_size": len(m.Message),
+		"topic":               m.Topic,
+		"message_id":          m.ID,
+		"message_sequence_id": m.SequenceID,
+		"message_time":        m.Time,
+		"message_event":       m.Event,
+		"message_body_size":   len(m.Message),
 	}
 	if m.Sender.IsValid() {
 		fields["message_sender"] = m.Sender.String()
@@ -61,6 +65,17 @@ func (m *message) Context() log.Context {
 	return fields
 }

+// forJSON returns a copy of the message suitable for JSON output.
+// It clears the SequenceID if it equals the ID to reduce redundancy.
+func (m *message) forJSON() *message {
+	if m.SequenceID == m.ID {
+		clone := *m
+		clone.SequenceID = ""
+		return &clone
+	}
+	return m
+}
+
 type attachment struct {
 	Name    string `json:"name"`
 	Type    string `json:"type,omitempty"`
@@ -91,22 +106,23 @@ func newAction() *action {

 // publishMessage is used as input when publishing as JSON
 type publishMessage struct {
-	Topic    string   `json:"topic"`
-	Title    string   `json:"title"`
-	Message  string   `json:"message"`
-	Priority int      `json:"priority"`
-	Tags     []string `json:"tags"`
-	Click    string   `json:"click"`
-	Icon     string   `json:"icon"`
-	Actions  []action `json:"actions"`
-	Attach   string   `json:"attach"`
-	Markdown bool     `json:"markdown"`
-	Filename string   `json:"filename"`
-	Email    string   `json:"email"`
-	Call     string   `json:"call"`
-	Cache    string   `json:"cache"`    // use string as it defaults to true (or use &bool instead)
-	Firebase string   `json:"firebase"` // use string as it defaults to true (or use &bool instead)
-	Delay    string   `json:"delay"`
+	Topic      string   `json:"topic"`
+	SequenceID string   `json:"sequence_id"`
+	Title      string   `json:"title"`
+	Message    string   `json:"message"`
+	Priority   int      `json:"priority"`
+	Tags       []string `json:"tags"`
+	Click      string   `json:"click"`
+	Icon       string   `json:"icon"`
+	Actions    []action `json:"actions"`
+	Attach     string   `json:"attach"`
+	Markdown   bool     `json:"markdown"`
+	Filename   string   `json:"filename"`
+	Email      string   `json:"email"`
+	Call       string   `json:"call"`
+	Cache      string   `json:"cache"`    // use string as it defaults to true (or use &bool instead)
+	Firebase   string   `json:"firebase"` // use string as it defaults to true (or use &bool instead)
+	Delay      string   `json:"delay"`
 }

 // messageEncoder is a function that knows how to encode a message
@@ -145,6 +161,13 @@ func newPollRequestMessage(topic, pollID string) *message {
 	return m
 }

+// newActionMessage creates a new action message (message_delete or message_clear)
+func newActionMessage(event, topic, sequenceID string) *message {
+	m := newMessage(event, topic, "")
+	m.SequenceID = sequenceID
+	return m
+}
+
 func validMessageID(s string) bool {
 	return util.ValidRandomString(s, messageIDLength)
 }
@@ -223,7 +246,7 @@ func parseQueryFilters(r *http.Request) (*queryFilter, error) {
 }

 func (q *queryFilter) Pass(msg *message) bool {
-	if msg.Event != messageEvent {
+	if msg.Event != messageEvent && msg.Event != messageDeleteEvent && msg.Event != messageClearEvent {
 		return true // filters only apply to messages
 	} else if q.ID != "" && msg.ID != q.ID {
 		return false
--- a/web/package-lock.json
+++ b/web/package-lock.json
--- a/web/public/static/langs/gl.json
+++ b/web/public/static/langs/gl.json
@@ -406,5 +406,7 @@
    "web_push_subscription_expiring_body": "Abrir ntfy para seguir recibindo notificacións",
    "web_push_unknown_notification_title": "Recibida unha notificación descoñecida desde o servidor",
    "web_push_unknown_notification_body": "Poderías ter que actualizar ntfy abrindo a app web",
-    "subscribe_dialog_subscribe_use_another_background_info": "As notificacións procedentes doutros servidores non se van recibir cando a app web estea pechada"
+    "subscribe_dialog_subscribe_use_another_background_info": "As notificacións procedentes doutros servidores non se van recibir cando a app web estea pechada",
+    "account_basics_cannot_edit_or_delete_provisioned_user": "Unha usuaria predefinida non se pode editar ou eliminar",
+    "account_tokens_table_cannot_delete_or_edit_provisioned_token": "Non se pode editar un token de usuaria predefinida"
 }
--- a/web/public/static/langs/id.json
+++ b/web/public/static/langs/id.json
@@ -50,7 +50,7 @@
    "publish_dialog_progress_uploading": "Mengunggah …",
    "notifications_more_details": "Untuk informasi lanjut, lihat <websiteLink>situs web</websiteLink> atau <docsLink>dokumentasi</docsLink>.",
    "publish_dialog_progress_uploading_detail": "Mengunggah {{loaded}}/{{total}} ({{percent}}%) …",
-    "publish_dialog_message_published": "Notifikasi terpublikasi",
+    "publish_dialog_message_published": "Notifikasi dipublikasi",
    "notifications_loading": "Memuat notifikasi …",
    "publish_dialog_base_url_label": "URL Layanan",
    "publish_dialog_title_placeholder": "Judul notifikasi, mis. Peringatan ruang disk",
@@ -71,9 +71,9 @@
    "publish_dialog_priority_high": "Prioritas tinggi",
    "publish_dialog_priority_max": "Prioritas maksimal",
    "publish_dialog_topic_label": "Nama topik",
-    "publish_dialog_message_placeholder": "Ketik sebuah pesan di sini",
+    "publish_dialog_message_placeholder": "Tulis pesan di sini",
    "publish_dialog_click_label": "Klik URL",
-    "publish_dialog_tags_placeholder": "Daftar tanda yang dipisah dengan koma, mis. peringatan, cadangan-srv1",
+    "publish_dialog_tags_placeholder": "Daftar label yang dipisah dengan tanda koma, contoh: peringatan, cadangan-srv1",
    "publish_dialog_click_placeholder": "URL yang dibuka ketika notifikasi diklik",
    "publish_dialog_email_label": "Email",
    "publish_dialog_email_placeholder": "Alamat untuk meneruskan notifikasi, mis. andi@contoh.com",
@@ -404,5 +404,7 @@
    "web_push_subscription_expiring_title": "Notifikasi akan dijeda",
    "web_push_subscription_expiring_body": "Buka ntfy untuk terus menerima notifikasi",
    "web_push_unknown_notification_title": "Notifikasi yang tidak diketahui diterima dari server",
-    "web_push_unknown_notification_body": "Anda mungkin harus memperbarui ntfy dengan membuka aplikasi web"
+    "web_push_unknown_notification_body": "Anda mungkin harus memperbarui ntfy dengan membuka aplikasi web",
+    "account_basics_cannot_edit_or_delete_provisioned_user": "Pengguna yang telah ditetapkan tidak dapat diedit atau dihapus",
+    "account_tokens_table_cannot_delete_or_edit_provisioned_token": "Tidak dapat mengedit atau menghapus token yang disediakan"
 }
--- a/web/public/static/langs/ja.json
+++ b/web/public/static/langs/ja.json
@@ -14,7 +14,7 @@
    "publish_dialog_title_no_topic": "通知を送信",
    "publish_dialog_progress_uploading": "アップロード中…",
    "publish_dialog_progress_uploading_detail": "アップロード中 {{loaded}}/{{total}} ({{percent}}%) …",
-    "publish_dialog_message_published": "通知を送信しました",
+    "publish_dialog_message_published": "通知送信済み",
    "publish_dialog_title_label": "タイトル",
    "publish_dialog_filename_label": "ファイル名",
    "subscribe_dialog_login_description": "このトピックはログインする必要があります。ユーザー名とパスワードを入力してください。",
@@ -69,10 +69,10 @@
    "publish_dialog_attachment_limits_quota_reached": "クォータを超過しました、残り{{remainingBytes}}",
    "publish_dialog_priority_high": "優先度 高",
    "publish_dialog_topic_placeholder": "トピック名の例 phil_alerts",
-    "publish_dialog_title_placeholder": "通知タイトル 例: ディスクスペース警告",
+    "publish_dialog_title_placeholder": "通知タイトル、例: ディスクスペース警告",
    "publish_dialog_message_placeholder": "メッセージ本文を入力してください",
    "publish_dialog_tags_label": "タグ",
-    "publish_dialog_tags_placeholder": "コンマ区切りでタグを列挙してください 例: warning, srv1-backup",
+    "publish_dialog_tags_placeholder": "コンマ区切りでタグを列挙してください、例: warning, srv1-backup",
    "publish_dialog_topic_label": "トピック名",
    "publish_dialog_delay_label": "遅延",
    "publish_dialog_click_placeholder": "通知をクリックしたときに開くURL",
--- a/web/public/static/langs/mk.json
+++ b/web/public/static/langs/mk.json
@@ -50,5 +50,47 @@
    "nav_topics_title": "Претплатени теми",
    "nav_button_all_notifications": "Сите нотификации",
    "nav_button_publish_message": "Објави нотификација",
-    "nav_button_subscribe": "Претплати се на тема"
+    "nav_button_subscribe": "Претплати се на тема",
+    "action_bar_unmute_notifications": "Одглуши ги нотификациите",
+    "action_bar_toggle_mute": "Заглуши/Загуши ги нотификациите",
+    "message_bar_publish": "Објави порака",
+    "nav_button_connecting": "се конектира",
+    "nav_upgrade_banner_label": "Надградете на ntfy Pro",
+    "nav_upgrade_banner_description": "Резервирајте теми, повеќе пораки и е-пораки и поголеми прилози",
+    "alert_notification_permission_required_title": "Известувањата се исклучени",
+    "alert_notification_permission_required_description": "Дајте му дозвола на вашиот прелистувач да прикажува известувања",
+    "nav_button_muted": "Известувањата се загушени",
+    "alert_not_supported_title": "Известувањата не се поддржани",
+    "alert_not_supported_description": "Известувањата не се поддржани во вашиот прелистувач",
+    "alert_not_supported_context_description": "Известувањата се поддржани само преку HTTPS. Ова е ограничување на <mdnLink>Notifications API </mdnLink>.",
+    "notifications_list": "Список на известувања",
+    "notifications_list_item": "Известување",
+    "notifications_mark_read": "Означи како прочитано",
+    "publish_dialog_attached_file_filename_placeholder": "Име на фајл за прилог",
+    "notifications_attachment_file_app": "Фајл со апликација за Android",
+    "notifications_attachment_file_document": "друг документ",
+    "alert_notification_permission_required_button": "Дајте дозвола сега",
+    "alert_notification_permission_denied_title": "Известувањата се блокирани",
+    "alert_notification_permission_denied_description": "Ве молиме повторно овозможете ги во вашиот пребарувач",
+    "alert_notification_ios_install_required_title": "Потребна е инсталација на iOS",
+    "alert_notification_ios_install_required_description": "Кликнете на иконата Сподели и Додај на почетниот екран за да овозможите известувања на iOS",
+    "notifications_delete": "Избриши",
+    "notifications_copied_to_clipboard": "Копирано во таблата со исечоци",
+    "notifications_tags": "Ознаки",
+    "notifications_priority_x": "Приоритет {{приоритет}}",
+    "notifications_new_indicator": "Ново известување",
+    "notifications_attachment_image": "Слика од прилог",
+    "notifications_attachment_copy_url_title": "Копирај URL-адресата на прилогот во таблата со исечоци",
+    "notifications_attachment_open_title": "Оди на {{url}}",
+    "notifications_attachment_open_button": "Отвори го прилогот",
+    "notifications_attachment_link_expires": "линкот истекува {{date}}",
+    "notifications_attachment_link_expired": "линкот за преземање е истечен",
+    "notifications_attachment_file_image": "слика фајл",
+    "notifications_attachment_file_video": "видео фајл",
+    "notifications_attachment_file_audio": "аудио фајл",
+    "notifications_click_copy_url_button": "Копирај линк",
+    "notifications_click_open_button": "Отвори линк",
+    "notifications_actions_open_url_title": "Оди на {{url}}",
+    "notifications_actions_not_supported": "Дејството не е поддржано во веб-апликацијата",
+    "notifications_actions_http_request_title": "Испрати HTTP {{method}} на {{url}}"
 }
--- a/web/public/static/langs/zh_Hans.json
+++ b/web/public/static/langs/zh_Hans.json
@@ -182,7 +182,7 @@
    "subscribe_dialog_subscribe_topic_placeholder": "主题名，例如 phil_alerts",
    "notifications_no_subscriptions_description": "单击 \"{{linktext}}\" 链接以创建或订阅主题。之后，您可以使用 PUT 或 POST 发送消息，您将在这里收到通知。",
    "publish_dialog_attachment_limits_file_reached": "超过 {{fileSizeLimit}} 文件限制",
-    "publish_dialog_title_placeholder": "主题标题，例如 磁盘空间告警",
+    "publish_dialog_title_placeholder": "通知标题，如磁盘空间告警",
    "publish_dialog_email_label": "电子邮件",
    "publish_dialog_button_send": "发送",
    "publish_dialog_checkbox_markdown": "格式化为 Markdown",
@@ -203,17 +203,17 @@
    "error_boundary_description": "这显然不应该发生。对此非常抱歉。<br/>如果您有时间，请<githubLink>在GitHub</githubLink>上报告，或通过<discordLink>Discord</discordLink>或<matrixLink>Matrix</matrixLink>告诉我们。",
    "prefs_users_table": "用户表",
    "prefs_users_edit_button": "编辑用户",
-    "publish_dialog_tags_placeholder": "英文逗号分隔标记列表，例如 warning, srv1-backup",
+    "publish_dialog_tags_placeholder": "英文逗号分隔的标签列表，例如 warning, srv1-backup",
    "publish_dialog_details_examples_description": "有关所有发送功能的示例和详细说明，请参阅<docsLink>文档</docsLink>。",
    "subscribe_dialog_subscribe_description": "主题可能不受密码保护，因此请选择一个不容易被猜中的名字。订阅后，您可以使用 PUT/POST 通知。",
-    "publish_dialog_delay_placeholder": "延期投递，例如 {{unixTimestamp}}、{{relativeTime}}或「{{naturalLanguage}}」（仅限英语）",
-    "account_usage_basis_ip_description": "此帐户的使用统计信息和限制基于您的 IP 地址，因此可能会与其他用户共享。上面显示的限制是基于现有速率限制的近似值。",
+    "publish_dialog_delay_placeholder": "延期投递，例如 {{unixTimestamp}}、{{relativeTime}} 或 {{naturalLanguage}} （仅限英语）",
+    "account_usage_basis_ip_description": "此账户的使用统计信息和限制基于您的 IP 地址，因此可能会与其他用户共享。上面显示的限制是基于现有速率限制的近似值。",
    "account_usage_cannot_create_portal_session": "无法打开计费门户",
-    "account_delete_title": "删除帐户",
-    "account_delete_description": "永久删除您的帐户",
+    "account_delete_title": "删除账户",
+    "account_delete_description": "永久删除您的账户",
    "signup_error_username_taken": "用户名 {{username}} 已被占用",
-    "signup_error_creation_limit_reached": "已达到帐户创建限制",
-    "login_title": "请登录你的 ntfy 帐户",
+    "signup_error_creation_limit_reached": "已达到账户创建限制",
+    "login_title": "请登录你的 ntfy 账户",
    "action_bar_change_display_name": "更改显示名称",
    "action_bar_reservation_add": "保留主题",
    "action_bar_reservation_delete": "移除保留",
@@ -223,7 +223,7 @@
    "action_bar_profile_logout": "登出",
    "action_bar_sign_in": "登录",
    "action_bar_sign_up": "注册",
-    "nav_button_account": "帐户",
+    "nav_button_account": "账户",
    "nav_upgrade_banner_label": "升级到 ntfy Pro",
    "nav_upgrade_banner_description": "保留主题，更多消息和邮件，以及更大的附件",
    "alert_not_supported_context_description": "通知仅支持 HTTPS。这是 <mdnLink>Notifications API</mdnLink> 的限制。",
@@ -233,7 +233,7 @@
    "reserve_dialog_checkbox_label": "保留主题并配置访问",
    "subscribe_dialog_subscribe_button_generate_topic_name": "生成名称",
    "account_basics_username_description": "嘿，那是你 ❤",
-    "account_basics_password_description": "更改您的帐户密码",
+    "account_basics_password_description": "更改您的账户密码",
    "account_basics_password_dialog_title": "更改密码",
    "account_basics_password_dialog_current_password_label": "当前密码",
    "account_basics_password_dialog_new_password_label": "新密码",
@@ -244,8 +244,8 @@
    "account_usage_of_limit": "{{limit}} 的",
    "account_usage_unlimited": "无限",
    "account_usage_limits_reset_daily": "使用限制每天午夜 (UTC) 重置",
-    "account_basics_tier_title": "帐户类型",
-    "account_basics_tier_description": "您帐户的权限级别",
+    "account_basics_tier_title": "账户类型",
+    "account_basics_tier_description": "您账户的权限级别",
    "account_basics_tier_admin": "管理员",
    "account_basics_tier_admin_suffix_with_tier": "（有 {{tier}} 等级）",
    "account_basics_tier_admin_suffix_no_tier": "（无等级）",
@@ -258,7 +258,7 @@
    "account_usage_messages_title": "已发布消息",
    "account_usage_emails_title": "已发送电子邮件",
    "account_usage_reservations_title": "保留主题",
-    "account_usage_reservations_none": "此帐户没有保留主题",
+    "account_usage_reservations_none": "此账户没有保留主题",
    "account_usage_attachment_storage_title": "附件存储",
    "account_usage_attachment_storage_description": "每个文件 {{filesize}}，在 {{expiry}} 后删除",
    "account_upgrade_dialog_button_pay_now": "立即付款并订阅",
@@ -276,7 +276,7 @@
    "account_tokens_delete_dialog_title": "删除访问令牌",
    "account_tokens_delete_dialog_description": "在删除访问令牌之前，请确保没有应用程序或脚本正在活跃使用它。 <strong>此操作无法撤消</strong>。",
    "account_tokens_delete_dialog_submit_button": "永久删除令牌",
-    "prefs_users_description_no_sync": "用户和密码不会同步到您的帐户。",
+    "prefs_users_description_no_sync": "用户和密码不会同步到您的账户。",
    "prefs_users_table_cannot_delete_or_edit": "无法删除或编辑已登录用户",
    "prefs_reservations_title": "保留主题",
    "prefs_reservations_description": "您可以在此处保留主题名称供个人使用。保留主题使您拥有该主题的所有权，并允许您为其他用户定义对该主题的访问权限。",
@@ -305,13 +305,13 @@
    "reservation_delete_dialog_action_delete_title": "删除缓存的邮件和附件",
    "reservation_delete_dialog_action_delete_description": "缓存的邮件和附件将被永久删除。此操作无法撤消。",
    "reservation_delete_dialog_submit_button": "删除保留",
-    "account_delete_dialog_description": "这将永久删除您的帐户，包括存储在服务器上的所有数据。删除后，您的用户名将在 7 天内不可用。如果您真的想继续，请在下面的框中使用您的密码进行确认。",
+    "account_delete_dialog_description": "这将永久删除您的账户，包括存储在服务器上的所有数据。删除后，您的用户名将在 7 天内不可用。如果您真的想继续，请在下面的框中使用您的密码进行确认。",
    "account_delete_dialog_label": "密码",
    "account_delete_dialog_button_cancel": "取消",
-    "account_delete_dialog_button_submit": "永久删除帐户",
-    "account_delete_dialog_billing_warning": "删除您的帐户也会立即取消您的计费订阅。您将无法再访问计费仪表板。",
-    "account_upgrade_dialog_title": "更改帐户等级",
-    "account_upgrade_dialog_cancel_warning": "这将<strong>取消您的订阅</strong>，并在 {{date}} 降级您的帐户。在那一天，主题保留以及缓存在服务器上的消息<strong>将被删除</strong>。",
+    "account_delete_dialog_button_submit": "永久删除账户",
+    "account_delete_dialog_billing_warning": "删除您的账户也会立即取消您的计费订阅。您将无法再访问计费仪表板。",
+    "account_upgrade_dialog_title": "更改账户等级",
+    "account_upgrade_dialog_cancel_warning": "这将<strong>取消您的订阅</strong>，并在 {{date}} 降级您的账户。在那一天，主题保留以及缓存在服务器上的消息<strong>将被删除</strong>。",
    "account_upgrade_dialog_proration_info": "<strong>按比例分配</strong>：在付费计划之间升级时，差价将被<strong>立刻收取</strong>。在降级到较低级别时，余额将被用于支付未来的账单周期。",
    "account_upgrade_dialog_reservations_warning_one": "所选等级允许的保留主题少于当前等级。在更改您的等级之前，<strong>请至少删除 1 项保留</strong>。您可以在<Link>设置</Link>中删除保留。",
    "account_upgrade_dialog_reservations_warning_other": "所选等级允许的保留主题少于当前等级。在更改您的等级之前，<strong>请至少删除 {{count}} 项保留</strong>。您可以在<Link>设置</Link>中删除保留。",
@@ -322,30 +322,30 @@
    "signup_form_confirm_password": "确认密码",
    "signup_form_button_submit": "注册",
    "signup_form_toggle_password_visibility": "切换密码可见性",
-    "signup_title": "创建一个 ntfy 帐户",
+    "signup_title": "创建一个 ntfy 账户",
    "signup_form_username": "用户名",
    "signup_form_password": "密码",
-    "signup_already_have_account": "已有帐户？登录！",
+    "signup_already_have_account": "已有账户？登录！",
    "signup_disabled": "注册已禁用",
    "login_form_button_submit": "登录",
    "login_link_signup": "注册",
    "login_disabled": "登录已禁用",
-    "action_bar_account": "帐户",
+    "action_bar_account": "账户",
    "action_bar_reservation_edit": "更改保留",
    "subscribe_dialog_error_topic_already_reserved": "主题已保留",
-    "account_basics_title": "帐户",
+    "account_basics_title": "账户",
    "account_basics_username_title": "用户名",
    "account_basics_username_admin_tooltip": "你是管理员",
    "account_basics_password_title": "密码",
-    "account_basics_tier_payment_overdue": "您的付款已逾期。请更新您的付款方式，否则您的帐户将很快被降级。",
-    "account_basics_tier_canceled_subscription": "您的订阅已取消，并将在 {{date}} 降级为免费帐户。",
+    "account_basics_tier_payment_overdue": "您的付款已逾期。请更新您的付款方式，否则您的账户将很快被降级。",
+    "account_basics_tier_canceled_subscription": "您的订阅已取消，并将在 {{date}} 降级为免费账户。",
    "account_upgrade_dialog_tier_features_attachment_total_size": "{{totalsize}} 总存储空间",
    "account_upgrade_dialog_tier_selected_label": "已选",
    "account_upgrade_dialog_tier_current_label": "当前",
    "account_upgrade_dialog_button_cancel": "取消",
    "account_upgrade_dialog_button_redirect_signup": "立即注册",
    "account_tokens_title": "访问令牌",
-    "account_tokens_description": "通过 ntfy API 发布和订阅时使用访问令牌，因此您不必发送您的帐户凭据。查看<Link>文档</Link>以了解更多信息。",
+    "account_tokens_description": "通过 ntfy API 发布和订阅时使用访问令牌，因此您不必发送您的账户凭据。查看<Link>文档</Link>以了解更多信息。",
    "account_tokens_table_token_header": "令牌",
    "account_tokens_table_label_header": "标签",
    "account_tokens_table_last_access_header": "最后访问",
@@ -403,5 +403,7 @@
    "web_push_subscription_expiring_title": "通知将被暂停",
    "web_push_subscription_expiring_body": "打开ntfy以继续接收通知",
    "web_push_unknown_notification_title": "接收到未知通知",
-    "web_push_unknown_notification_body": "你可能需要打开网页来更新ntfy"
+    "web_push_unknown_notification_body": "你可能需要打开网页来更新ntfy",
+    "account_basics_cannot_edit_or_delete_provisioned_user": "已设置的用户无法被编辑或删除",
+    "account_tokens_table_cannot_delete_or_edit_provisioned_token": "无法编辑或删除已设置的令牌"
 }
--- a/web/public/static/langs/zh_Hant.json
+++ b/web/public/static/langs/zh_Hant.json
@@ -403,5 +403,7 @@
    "web_push_subscription_expiring_body": "開啟ntfy以繼續接收通知",
    "web_push_subscription_expiring_title": "通知會被暫停",
    "web_push_unknown_notification_body": "你可能需要開啟網頁來更新ntfy",
-    "web_push_unknown_notification_title": "接收到不明通知"
+    "web_push_unknown_notification_title": "接收到不明通知",
+    "account_basics_cannot_edit_or_delete_provisioned_user": "已佈建的使用者無法編輯或刪除",
+    "account_tokens_table_cannot_delete_or_edit_provisioned_token": "無法編輯或刪除已佈建的權杖"
 }
--- a/web/public/sw.js
+++ b/web/public/sw.js
@@ -3,11 +3,16 @@ import { cleanupOutdatedCaches, createHandlerBoundToURL, precacheAndRoute } from
 import { NavigationRoute, registerRoute } from "workbox-routing";
 import { NetworkFirst } from "workbox-strategies";
 import { clientsClaim } from "workbox-core";
-
 import { dbAsync } from "../src/app/db";
-
-import { toNotificationParams, icon, badge } from "../src/app/notificationUtils";
+import { badge, icon, messageWithSequenceId, toNotificationParams } from "../src/app/notificationUtils";
 import initI18n from "../src/app/i18n";
+import {
+  EVENT_MESSAGE,
+  EVENT_MESSAGE_CLEAR,
+  EVENT_MESSAGE_DELETE,
+  WEBPUSH_EVENT_MESSAGE,
+  WEBPUSH_EVENT_SUBSCRIPTION_EXPIRING,
+} from "../src/app/events";

 /**
 * General docs for service workers and PWAs:
@@ -21,25 +26,6 @@ import initI18n from "../src/app/i18n";

 const broadcastChannel = new BroadcastChannel("web-push-broadcast");

-const addNotification = async ({ subscriptionId, message }) => {
-  const db = await dbAsync();
-
-  await db.notifications.add({
-    ...message,
-    subscriptionId,
-    // New marker (used for bubble indicator); cannot be boolean; Dexie index limitation
-    new: 1,
-  });
-
-  await db.subscriptions.update(subscriptionId, {
-    last: message.id,
-  });
-
-  const badgeCount = await db.notifications.where({ new: 1 }).count();
-  console.log("[ServiceWorker] Setting new app badge count", { badgeCount });
-  self.navigator.setAppBadge?.(badgeCount);
-};
-
 /**
 * Handle a received web push message and show notification.
 *
@@ -48,10 +34,35 @@ const addNotification = async ({ subscriptionId, message }) => {
 */
 const handlePushMessage = async (data) => {
  const { subscription_id: subscriptionId, message } = data;
+  const db = await dbAsync();

-  broadcastChannel.postMessage(message); // To potentially play sound
+  console.log("[ServiceWorker] Message received", data);
+
+  // Delete existing notification with same sequence ID (if any)
+  const sequenceId = message.sequence_id || message.id;
+  if (sequenceId) {
+    await db.notifications.where({ subscriptionId, sequenceId }).delete();
+  }
+
+  // Add notification to database
+  await db.notifications.add({
+    ...messageWithSequenceId(message),
+    subscriptionId,
+    new: 1, // New marker (used for bubble indicator); cannot be boolean; Dexie index limitation
+  });
+
+  // Update subscription last message id (for ?since=... queries)
+  await db.subscriptions.update(subscriptionId, {
+    last: message.id,
+  });
+
+  // Update badge in PWA
+  const badgeCount = await db.notifications.where({ new: 1 }).count();
+  self.navigator.setAppBadge?.(badgeCount);
+
+  // Broadcast the message to potentially play a sound
+  broadcastChannel.postMessage(message);

-  await addNotification({ subscriptionId, message });
  await self.registration.showNotification(
    ...toNotificationParams({
      subscriptionId,
@@ -62,11 +73,70 @@ const handlePushMessage = async (data) => {
  );
 };

+/**
+ * Handle a message_delete event: delete the notification from the database.
+ */
+const handlePushMessageDelete = async (data) => {
+  const { subscription_id: subscriptionId, message } = data;
+  const db = await dbAsync();
+  console.log("[ServiceWorker] Deleting notification sequence", data);
+
+  // Delete notification with the same sequence_id
+  const sequenceId = message.sequence_id;
+  if (sequenceId) {
+    await db.notifications.where({ subscriptionId, sequenceId }).delete();
+  }
+
+  // Close browser notification with matching tag
+  const tag = message.sequence_id || message.id;
+  if (tag) {
+    const notifications = await self.registration.getNotifications({ tag });
+    notifications.forEach((notification) => notification.close());
+  }
+
+  // Update subscription last message id (for ?since=... queries)
+  await db.subscriptions.update(subscriptionId, {
+    last: message.id,
+  });
+};
+
+/**
+ * Handle a message_clear event: clear/dismiss the notification.
+ */
+const handlePushMessageClear = async (data) => {
+  const { subscription_id: subscriptionId, message } = data;
+  const db = await dbAsync();
+  console.log("[ServiceWorker] Marking notification as read", data);
+
+  // Mark notification as read (set new = 0)
+  const sequenceId = message.sequence_id;
+  if (sequenceId) {
+    await db.notifications.where({ subscriptionId, sequenceId }).modify({ new: 0 });
+  }
+
+  // Close browser notification with matching tag
+  const tag = message.sequence_id || message.id;
+  if (tag) {
+    const notifications = await self.registration.getNotifications({ tag });
+    notifications.forEach((notification) => notification.close());
+  }
+
+  // Update subscription last message id (for ?since=... queries)
+  await db.subscriptions.update(subscriptionId, {
+    last: message.id,
+  });
+
+  // Update badge count
+  const badgeCount = await db.notifications.where({ new: 1 }).count();
+  self.navigator.setAppBadge?.(badgeCount);
+};
+
 /**
 * Handle a received web push subscription expiring.
 */
 const handlePushSubscriptionExpiring = async (data) => {
  const t = await initI18n();
+  console.log("[ServiceWorker] Handling incoming subscription expiring event", data);

  await self.registration.showNotification(t("web_push_subscription_expiring_title"), {
    body: t("web_push_subscription_expiring_body"),
@@ -82,6 +152,7 @@ const handlePushSubscriptionExpiring = async (data) => {
 */
 const handlePushUnknown = async (data) => {
  const t = await initI18n();
+  console.log("[ServiceWorker] Unknown event received", data);

  await self.registration.showNotification(t("web_push_unknown_notification_title"), {
    body: t("web_push_unknown_notification_body"),
@@ -96,13 +167,26 @@ const handlePushUnknown = async (data) => {
 * @param {object} data see server/types.go, type webPushPayload
 */
 const handlePush = async (data) => {
-  if (data.event === "message") {
-    await handlePushMessage(data);
-  } else if (data.event === "subscription_expiring") {
-    await handlePushSubscriptionExpiring(data);
-  } else {
-    await handlePushUnknown(data);
+  // This logic is (partially) duplicated in
+  // - Android: SubscriberService::onNotificationReceived()
+  // - Android: FirebaseService::onMessageReceived()
+  // - Web app: hooks.js:handleNotification()
+  // - Web app: sw.js:handleMessage(), sw.js:handleMessageClear(), ...
+
+  if (data.event === WEBPUSH_EVENT_MESSAGE) {
+    const { message } = data;
+    if (message.event === EVENT_MESSAGE) {
+      return await handlePushMessage(data);
+    } else if (message.event === EVENT_MESSAGE_DELETE) {
+      return await handlePushMessageDelete(data);
+    } else if (message.event === EVENT_MESSAGE_CLEAR) {
+      return await handlePushMessageClear(data);
+    }
+  } else if (data.event === WEBPUSH_EVENT_SUBSCRIPTION_EXPIRING) {
+    return await handlePushSubscriptionExpiring(data);
  }
+
+  return await handlePushUnknown(data);
 };

 /**
@@ -113,10 +197,8 @@ const handleClick = async (event) => {
  const t = await initI18n();

  const clients = await self.clients.matchAll({ type: "window" });
-
  const rootUrl = new URL(self.location.origin);
  const rootClient = clients.find((client) => client.url === rootUrl.toString());
-  // perhaps open on another topic
  const fallbackClient = clients[0];

  if (!event.notification.data?.message) {
@@ -232,6 +314,7 @@ precacheAndRoute(

 // Claim all open windows
 clientsClaim();
+
 // Delete any cached old dist files from previous service worker versions
 cleanupOutdatedCaches();

--- a/web/src/app/Connection.js
+++ b/web/src/app/Connection.js
@@ -1,5 +1,6 @@
 /* eslint-disable max-classes-per-file */
 import { basicAuth, bearerAuth, encodeBase64Url, topicShortUrl, topicUrlWs } from "./utils";
+import { EVENT_OPEN, isNotificationEvent } from "./events";

 const retryBackoffSeconds = [5, 10, 20, 30, 60, 120];

@@ -48,10 +49,11 @@ class Connection {
      console.log(`[Connection, ${this.shortUrl}, ${this.connectionId}] Message received from server: ${event.data}`);
      try {
        const data = JSON.parse(event.data);
-        if (data.event === "open") {
+        if (data.event === EVENT_OPEN) {
          return;
        }
-        const relevantAndValid = data.event === "message" && "id" in data && "time" in data && "message" in data;
+        // Accept message, message_delete, and message_clear events
+        const relevantAndValid = isNotificationEvent(data.event) && "id" in data && "time" in data;
        if (!relevantAndValid) {
          console.log(`[Connection, ${this.shortUrl}, ${this.connectionId}] Unexpected message. Ignoring.`);
          return;
--- a/web/src/app/Notifier.js
+++ b/web/src/app/Notifier.js
@@ -31,6 +31,21 @@ class Notifier {
    );
  }

+  async cancel(notification) {
+    if (!this.supported()) {
+      return;
+    }
+    try {
+      const tag = notification.sequence_id || notification.id;
+      console.log(`[Notifier] Cancelling notification with ${tag}`);
+      const registration = await this.serviceWorkerRegistration();
+      const notifications = await registration.getNotifications({ tag });
+      notifications.forEach((n) => n.close());
+    } catch (e) {
+      console.log(`[Notifier] Error cancelling notification`, e);
+    }
+  }
+
  async playSound() {
    // Play sound
    const sound = await prefs.sound();
--- a/web/src/app/Poller.js
+++ b/web/src/app/Poller.js
@@ -1,5 +1,7 @@
 import api from "./Api";
+import prefs from "./Prefs";
 import subscriptionManager from "./SubscriptionManager";
+import { EVENT_MESSAGE, EVENT_MESSAGE_DELETE } from "./events";

 const delayMillis = 2000; // 2 seconds
 const intervalMillis = 300000; // 5 minutes
@@ -42,12 +44,35 @@ class Poller {

    const since = subscription.last;
    const notifications = await api.poll(subscription.baseUrl, subscription.topic, since);
-    if (!notifications || notifications.length === 0) {
-      console.log(`[Poller] No new notifications found for ${subscription.id}`);
-      return;
+
+    // Filter out notifications older than the prune threshold
+    const deleteAfterSeconds = await prefs.deleteAfter();
+    const pruneThresholdTimestamp = deleteAfterSeconds > 0 ? Math.round(Date.now() / 1000) - deleteAfterSeconds : 0;
+    const recentNotifications =
+      pruneThresholdTimestamp > 0 ? notifications.filter((n) => n.time >= pruneThresholdTimestamp) : notifications;
+
+    // Find the latest notification for each sequence ID
+    const latestBySequenceId = this.latestNotificationsBySequenceId(recentNotifications);
+
+    // Delete all existing notifications for which the latest notification is marked as deleted
+    const deletedSequenceIds = Object.entries(latestBySequenceId)
+      .filter(([, notification]) => notification.event === EVENT_MESSAGE_DELETE)
+      .map(([sequenceId]) => sequenceId);
+    if (deletedSequenceIds.length > 0) {
+      console.log(`[Poller] Deleting notifications with deleted sequence IDs for ${subscription.id}`, deletedSequenceIds);
+      await Promise.all(
+        deletedSequenceIds.map((sequenceId) => subscriptionManager.deleteNotificationBySequenceId(subscription.id, sequenceId))
+      );
+    }
+
+    // Add only the latest notification for each non-deleted sequence
+    const notificationsToAdd = Object.values(latestBySequenceId).filter((n) => n.event === EVENT_MESSAGE);
+    if (notificationsToAdd.length > 0) {
+      console.log(`[Poller] Adding ${notificationsToAdd.length} notification(s) for ${subscription.id}`);
+      await subscriptionManager.addNotifications(subscription.id, notificationsToAdd);
+    } else {
+      console.log(`[Poller] No new notifications found for ${subscription.id}`);
    }
-    console.log(`[Poller] Adding ${notifications.length} notification(s) for ${subscription.id}`);
-    await subscriptionManager.addNotifications(subscription.id, notifications);
  }

  pollInBackground(subscription) {
@@ -59,6 +84,21 @@ class Poller {
      }
    })();
  }
+
+  /**
+   * Groups notifications by sequenceId and returns only the latest (highest time) for each sequence.
+   * Returns an object mapping sequenceId -> latest notification.
+   */
+  latestNotificationsBySequenceId(notifications) {
+    const latestBySequenceId = {};
+    notifications.forEach((notification) => {
+      const sequenceId = notification.sequence_id || notification.id;
+      if (!(sequenceId in latestBySequenceId) || notification.time >= latestBySequenceId[sequenceId].time) {
+        latestBySequenceId[sequenceId] = notification;
+      }
+    });
+    return latestBySequenceId;
+  }
 }

 const poller = new Poller();
--- a/web/src/app/SubscriptionManager.js
+++ b/web/src/app/SubscriptionManager.js
@@ -3,6 +3,8 @@ import notifier from "./Notifier";
 import prefs from "./Prefs";
 import db from "./db";
 import { topicUrl } from "./utils";
+import { messageWithSequenceId } from "./notificationUtils";
+import { EVENT_MESSAGE, EVENT_MESSAGE_CLEAR, EVENT_MESSAGE_DELETE } from "./events";

 class SubscriptionManager {
  constructor(dbImpl) {
@@ -48,16 +50,17 @@ class SubscriptionManager {
  }

  async notify(subscriptionId, notification) {
+    if (notification.event !== EVENT_MESSAGE) {
+      return;
+    }
    const subscription = await this.get(subscriptionId);
    if (subscription.mutedUntil > 0) {
      return;
    }
-
    const priority = notification.priority ?? 3;
    if (priority < (await prefs.minPriority())) {
      return;
    }
-
    await notifier.notify(subscription, notification);
  }

@@ -157,7 +160,7 @@ class SubscriptionManager {
    // killing performance. See  https://dexie.org/docs/Collection/Collection.offset()#a-better-paging-approach

    return this.db.notifications
-      .orderBy("time") // Sort by time first
+      .orderBy("time") // Sort by time
      .filter((n) => n.subscriptionId === subscriptionId)
      .reverse()
      .toArray();
@@ -173,17 +176,22 @@ class SubscriptionManager {
  /** Adds notification, or returns false if it already exists */
  async addNotification(subscriptionId, notification) {
    const exists = await this.db.notifications.get(notification.id);
-    if (exists) {
+    if (exists || notification.event === EVENT_MESSAGE_DELETE || notification.event === EVENT_MESSAGE_CLEAR) {
      return false;
    }
    try {
-      // sw.js duplicates this logic, so if you change it here, change it there too
+      // Note: Service worker (sw.js) and addNotifications() duplicates this logic,
+      // so if you change it here, change it there too.
+
+      // Add notification to database
      await this.db.notifications.add({
-        ...notification,
+        ...messageWithSequenceId(notification),
        subscriptionId,
-        // New marker (used for bubble indicator); cannot be boolean; Dexie index limitation
-        new: 1,
-      }); // FIXME consider put() for double tab
+        new: 1, // New marker (used for bubble indicator); cannot be boolean; Dexie index limitation
+      });
+
+      // FIXME consider put() for double tab
+      // Update subscription last message id (for ?since=... queries)
      await this.db.subscriptions.update(subscriptionId, {
        last: notification.id,
      });
@@ -195,7 +203,10 @@ class SubscriptionManager {

  /** Adds/replaces notifications, will not throw if they exist */
  async addNotifications(subscriptionId, notifications) {
-    const notificationsWithSubscriptionId = notifications.map((notification) => ({ ...notification, subscriptionId }));
+    const notificationsWithSubscriptionId = notifications.map((notification) => ({
+      ...messageWithSequenceId(notification),
+      subscriptionId,
+    }));
    const lastNotificationId = notifications.at(-1).id;
    await this.db.notifications.bulkPut(notificationsWithSubscriptionId);
    await this.db.subscriptions.update(subscriptionId, {
@@ -220,6 +231,10 @@ class SubscriptionManager {
    await this.db.notifications.delete(notificationId);
  }

+  async deleteNotificationBySequenceId(subscriptionId, sequenceId) {
+    await this.db.notifications.where({ subscriptionId, sequenceId }).delete();
+  }
+
  async deleteNotifications(subscriptionId) {
    await this.db.notifications.where({ subscriptionId }).delete();
  }
@@ -228,6 +243,10 @@ class SubscriptionManager {
    await this.db.notifications.where({ id: notificationId }).modify({ new: 0 });
  }

+  async markNotificationReadBySequenceId(subscriptionId, sequenceId) {
+    await this.db.notifications.where({ subscriptionId, sequenceId }).modify({ new: 0 });
+  }
+
  async markNotificationsRead(subscriptionId) {
    await this.db.notifications.where({ subscriptionId, new: 1 }).modify({ new: 0 });
  }
--- a/web/src/app/db.js
+++ b/web/src/app/db.js
@@ -11,13 +11,20 @@ const createDatabase = (username) => {
  const dbName = username ? `ntfy-${username}` : "ntfy"; // IndexedDB database is based on the logged-in user
  const db = new Dexie(dbName);

-  db.version(2).stores({
+  db.version(3).stores({
    subscriptions: "&id,baseUrl,[baseUrl+mutedUntil]",
-    notifications: "&id,subscriptionId,time,new,[subscriptionId+new]", // compound key for query performance
+    notifications: "&id,sequenceId,subscriptionId,time,new,[subscriptionId+new],[subscriptionId+sequenceId]",
    users: "&baseUrl,username",
    prefs: "&key",
  });

+  // When another connection (e.g., service worker or another tab) wants to upgrade,
+  // close this connection gracefully to allow the upgrade to proceed
+  db.on("versionchange", () => {
+    console.log("[db] versionchange event: closing database");
+    db.close();
+  });
+
  return db;
 };

--- a/web/src/app/events.js
+++ b/web/src/app/events.js
@@ -0,0 +1,15 @@
+// Event types for ntfy messages
+// These correspond to the server event types in server/types.go
+
+export const EVENT_OPEN = "open";
+export const EVENT_KEEPALIVE = "keepalive";
+export const EVENT_MESSAGE = "message";
+export const EVENT_MESSAGE_DELETE = "message_delete";
+export const EVENT_MESSAGE_CLEAR = "message_clear";
+export const EVENT_POLL_REQUEST = "poll_request";
+
+export const WEBPUSH_EVENT_MESSAGE = "message";
+export const WEBPUSH_EVENT_SUBSCRIPTION_EXPIRING = "subscription_expiring";
+
+// Check if an event is a notification event (message, delete, or read)
+export const isNotificationEvent = (event) => event === EVENT_MESSAGE || event === EVENT_MESSAGE_DELETE || event === EVENT_MESSAGE_CLEAR;
--- a/web/src/app/notificationUtils.js
+++ b/web/src/app/notificationUtils.js
@@ -25,13 +25,13 @@ const formatTitleWithDefault = (m, fallback) => {

 export const formatMessage = (m) => {
  if (m.title) {
-    return m.message;
+    return m.message || "";
  }
  const emojiList = toEmojis(m.tags);
  if (emojiList.length > 0) {
-    return `${emojiList.join(" ")} ${m.message}`;
+    return `${emojiList.join(" ")} ${m.message || ""}`;
  }
-  return m.message;
+  return m.message || "";
 };

 const imageRegex = /\.(png|jpe?g|gif|webp)$/i;
@@ -50,7 +50,7 @@ export const isImage = (attachment) => {
 export const icon = "/static/images/ntfy.png";
 export const badge = "/static/images/mask-icon.svg";

-export const toNotificationParams = ({ subscriptionId, message, defaultTitle, topicRoute }) => {
+export const toNotificationParams = ({ message, defaultTitle, topicRoute }) => {
  const image = isImage(message.attachment) ? message.attachment.url : undefined;

  // https://developer.mozilla.org/en-US/docs/Web/API/Notifications_API
@@ -61,8 +61,8 @@ export const toNotificationParams = ({ subscriptionId, message, defaultTitle, to
      badge,
      icon,
      image,
-      timestamp: message.time * 1_000,
-      tag: subscriptionId,
+      timestamp: message.time * 1000,
+      tag: message.sequence_id || message.id, // Update notification if there is a sequence ID
      renotify: true,
      silent: false,
      // This is used by the notification onclick event
@@ -79,3 +79,10 @@ export const toNotificationParams = ({ subscriptionId, message, defaultTitle, to
    },
  ];
 };
+
+export const messageWithSequenceId = (message) => {
+  if (message.sequenceId) {
+    return message;
+  }
+  return { ...message, sequenceId: message.sequence_id || message.id };
+};
--- a/web/src/components/hooks.js
+++ b/web/src/components/hooks.js
@@ -12,6 +12,7 @@ import accountApi from "../app/AccountApi";
 import { UnauthorizedError } from "../app/errors";
 import notifier from "../app/Notifier";
 import prefs from "../app/Prefs";
+import { EVENT_MESSAGE_DELETE, EVENT_MESSAGE_CLEAR } from "../app/events";

 /**
 * Wire connectionManager and subscriptionManager so that subscriptions are updated when the connection
@@ -50,9 +51,28 @@ export const useConnectionListeners = (account, subscriptions, users, webPushTop
      };

      const handleNotification = async (subscriptionId, notification) => {
-        const added = await subscriptionManager.addNotification(subscriptionId, notification);
-        if (added) {
-          await subscriptionManager.notify(subscriptionId, notification);
+        // This logic is (partially) duplicated in
+        // - Android: SubscriberService::onNotificationReceived()
+        // - Android: FirebaseService::onMessageReceived()
+        // - Web app: hooks.js:handleNotification()
+        // - Web app: sw.js:handleMessage(), sw.js:handleMessageClear(), ...
+
+        if (notification.event === EVENT_MESSAGE_DELETE && notification.sequence_id) {
+          await subscriptionManager.deleteNotificationBySequenceId(subscriptionId, notification.sequence_id);
+          await notifier.cancel(notification);
+        } else if (notification.event === EVENT_MESSAGE_CLEAR && notification.sequence_id) {
+          await subscriptionManager.markNotificationReadBySequenceId(subscriptionId, notification.sequence_id);
+          await notifier.cancel(notification);
+        } else {
+          // Regular message: delete existing and add new
+          const sequenceId = notification.sequence_id || notification.id;
+          if (sequenceId) {
+            await subscriptionManager.deleteNotificationBySequenceId(subscriptionId, sequenceId);
+          }
+          const added = await subscriptionManager.addNotification(subscriptionId, notification);
+          if (added) {
+            await subscriptionManager.notify(subscriptionId, notification);
+          }
        }
      };

@@ -231,7 +251,9 @@ export const useIsLaunchedPWA = () => {

  useEffect(() => {
    if (isIOSStandalone) {
-      return () => {}; // No need to listen for events on iOS
+      return () => {
+        // No need to listen for events on iOS
+      };
    }
    const handler = (evt) => {
      console.log(`[useIsLaunchedPWA] App is now running ${evt.matches ? "standalone" : "in the browser"}`);
--- a/web/src/registerSW.js
+++ b/web/src/registerSW.js
@@ -5,10 +5,19 @@ import { registerSW as viteRegisterSW } from "virtual:pwa-register";
 const intervalMS = 60 * 60 * 1000;

 // https://vite-pwa-org.netlify.app/guide/periodic-sw-updates.html
-const registerSW = () =>
+const registerSW = () => {
+  console.log("[ServiceWorker] Registering service worker");
+  if (!("serviceWorker" in navigator)) {
+    console.warn("[ServiceWorker] Service workers not supported");
+    return;
+  }
+
  viteRegisterSW({
    onRegisteredSW(swUrl, registration) {
+      console.log("[ServiceWorker] Registered:", { swUrl, registration });
+
      if (!registration) {
+        console.warn("[ServiceWorker] No registration returned");
        return;
      }

@@ -23,9 +32,16 @@ const registerSW = () =>
          },
        });

-        if (resp?.status === 200) await registration.update();
+        if (resp?.status === 200) {
+          console.log("[ServiceWorker] Updating service worker");
+          await registration.update();
+        }
      }, intervalMS);
    },
+    onRegisterError(error) {
+      console.error("[ServiceWorker] Registration error:", error);
+    },
  });
+};

 export default registerSW;
Author	SHA1	Message	Date
binwiederhier	c1ee163cab	Remove cache thing	2026-01-16 10:07:09 -05:00
binwiederhier	fcf57a04e1	Move event up	2026-01-16 09:36:27 -05:00
binwiederhier	0ad06e808f	Self-review	2026-01-15 22:14:56 -05:00
binwiederhier	2cc4bf7d28	Fix webpush stuff	2026-01-15 21:55:20 -05:00
binwiederhier	5ae3774f19	Refine, docs	2026-01-15 19:06:05 -05:00
binwiederhier	94eb121f38	Docs updates	2026-01-15 13:07:07 -05:00
binwiederhier	e81be48bf3	MOre docs update	2026-01-15 10:32:48 -05:00
binwiederhier	db4a4776d3	Reword	2026-01-15 10:07:05 -05:00
binwiederhier	3d54260f79	Docs	2026-01-15 09:30:37 -05:00
binwiederhier	ea3008c707	Move, add screenshots	2026-01-14 22:18:57 -05:00
binwiederhier	2e39a1329c	AI docs, needs work	2026-01-14 21:48:21 -05:00
binwiederhier	ff2b8167b4	Make closing notifications work	2026-01-14 21:17:21 -05:00
binwiederhier	96638b516c	Fix service worker handling for updating/deleting	2026-01-14 20:46:18 -05:00
binwiederhier	dd9b36cf0a	Fix db crash	2026-01-13 21:29:44 -05:00
binwiederhier	44f20f6b4c	Add tests, fix firebase	2026-01-13 20:50:31 -05:00
binwiederhier	a3c16d81f8	Rename to clear	2026-01-13 16:31:13 -05:00
binwiederhier	b5f24b12dc	Merge branch 'main' of github.com:binwiederhier/ntfy into 303-update-notifications	2026-01-12 21:38:55 -05:00
binwiederhier	898a52ec63	Merge branch 'main' of github.com:binwiederhier/ntfy	2026-01-11 09:27:01 -05:00
binwiederhier	7066ba92a6	Merge branch 'main' of https://hosted.weblate.org/git/ntfy/web	2026-01-11 09:26:58 -05:00
binwiederhier	8960459520	Changelog	2026-01-11 09:26:44 -05:00
$Kristijan \"Fremen\" Velkovski$ Kristijan \"Fremen\" Velkovski	f581af6d27	Translated using Weblate (Macedonian) Currently translated at 23.0% (94 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/mk/	2026-01-11 07:01:51 +00:00
Shoshin Akamine	88016a2549	Translated using Weblate (Japanese) Currently translated at 100.0% (407 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/ja/	2026-01-11 07:01:49 +00:00
大王叫我来巡山	a7603d1dfb	Translated using Weblate (Chinese (Simplified Han script)) Currently translated at 100.0% (407 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/zh_Hans/	2026-01-11 07:01:47 +00:00
Philipp C. Heckel	65e2af9efb	Merge pull request #1542 from ecntu/fix-typos fix typos in docs	2026-01-10 22:29:22 -05:00
Emilio Cantú	090cd720c1	fix typos	2026-01-10 22:03:41 -05:00
binwiederhier	7bc8edf7c3	Bump, release notes	2026-01-10 20:47:59 -05:00
$Kristijan \"Fremen\" Velkovski$ Kristijan \"Fremen\" Velkovski	13768d4289	Translated using Weblate (Macedonian) Currently translated at 16.4% (67 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/mk/	2026-01-10 05:01:49 +01:00
binwiederhier	37d71051de	Refine	2026-01-08 20:57:55 -05:00
binwiederhier	5ad3de2904	Switch to event type	2026-01-08 20:50:23 -05:00
binwiederhier	66ea25c18b	Add JSON publishing support	2026-01-08 15:45:50 -05:00
binwiederhier	1ab7ca876c	Rename to sequence_id	2026-01-08 14:27:18 -05:00
binwiederhier	fd8cd5ca91	Comment	2026-01-08 13:45:05 -05:00
binwiederhier	7cffbfcd6d	Simplify handleNotifications	2026-01-08 13:43:57 -05:00
binwiederhier	dffee9ea7d	Remove forJSON	2026-01-08 11:39:32 -05:00
binwiederhier	239959e2a4	Revert some changes; make poller respect deleteAfter pref	2026-01-08 11:19:53 -05:00
binwiederhier	75abf2e245	Delete old messages with SID when new messages arrive	2026-01-08 10:28:02 -05:00
binwiederhier	bfbe73aea3	Update polling	2026-01-07 09:46:08 -05:00
$Kristijan \"Fremen\" Velkovski$ Kristijan \"Fremen\" Velkovski	b3721c1b71	Translated using Weblate (Macedonian) Currently translated at 14.7% (60 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/mk/	2026-01-07 14:01:52 +00:00
cyberboh	544f7ef1cb	Translated using Weblate (Indonesian) Currently translated at 100.0% (407 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/id/	2026-01-07 14:01:47 +00:00
binwiederhier	2dd152df3f	Manual fixes for AI slop	2026-01-06 18:02:08 -05:00
binwiederhier	2856793eff	Deleted	2026-01-06 14:22:55 -05:00
$Kristijan \"Fremen\" Velkovski$ Kristijan \"Fremen\" Velkovski	16bec00b38	Translated using Weblate (Macedonian) Currently translated at 13.5% (55 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/mk/	2026-01-06 06:01:47 +00:00
binwiederhier	f51e99dc80	Remove modified	2026-01-05 21:55:07 -05:00
binwiederhier	aca9a77498	Remove mtime	2026-01-05 21:14:29 -05:00
binwiederhier	1c2550d749	Merge branch 'main' into 303-update-notifications	2026-01-05 15:34:42 -05:00
binwiederhier	e18d64933f	Release notes	2026-01-04 10:57:11 -05:00
josé m.	20ccee5d7d	Translated using Weblate (Galician) Currently translated at 100.0% (407 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/gl/	2026-01-04 16:01:47 +01:00
binwiederhier	3575abcde3	Restructure contact page	2026-01-02 08:10:34 -05:00
binwiederhier	2cd444ece0	Contact page	2026-01-02 08:05:39 -05:00
binwiederhier	eca1ed4d8d	Contact and contributing page	2026-01-02 07:59:02 -05:00
binwiederhier	4ce9508fd3	Privacy policy commit history	2026-01-02 07:44:39 -05:00
binwiederhier	4f9f1292f1	Update privacy policy	2026-01-02 07:35:06 -05:00
binwiederhier	d64376c5ac	Merge branch 'main' of https://hosted.weblate.org/git/ntfy/web	2026-01-01 21:49:37 -05:00
binwiederhier	275487b3fd	Release notes	2026-01-01 21:49:26 -05:00
ezn24	9301546e6d	Translated using Weblate (Chinese (Traditional Han script)) Currently translated at 100.0% (407 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/zh_Hant/	2026-01-01 20:01:47 +01:00
大王叫我来巡山	49b3c724cf	Translated using Weblate (Chinese (Simplified Han script)) Currently translated at 100.0% (407 of 407 strings) Translation: ntfy/Web app Translate-URL: https://hosted.weblate.org/projects/ntfy/web/zh_Hans/	2025-12-31 15:03:58 +01:00
Philipp C. Heckel	7091775234	Merge pull request #1527 from cbrake/main add BRun to list of integrations	2025-12-30 17:24:41 -05:00
Cliff Brake	90667e7176	add BRun to list of integrations	2025-12-30 17:19:07 -05:00
Hunter Kehoe	8293a24cf9	update notification text using sid in web app	2025-10-17 22:10:11 -06:00
Hunter Kehoe	83b5470bc5	publish messages with a custom sequence ID	2025-10-17 19:01:41 -06:00
Hunter Kehoe	2aae3577cb	add sid, mtime, and deleted to message_cache	2025-10-17 17:39:55 -06:00