Notification Actions 'Mark As Read' and 'Delete' Stop Functioning When Message List Widget Is Added in Android 16

Checklist

• I have used the search function to see if someone else has already submitted the same bug report.
• I will describe the problem with as much detail as possible.

App

Thunderbird for Android

App version

16.1

Where did you get the app from?

Google Play

Android version

16

Device model

OnePlus 13

Steps to reproduce

1. Receive new email notification
2. Press 'Mark as Read' button on notification
3. Observe correct functionality (notification is dismissed, message marked as read)
4. Add 'Message List' widget to home screen
5. Receive new email notification
6. Press 'Mark as Read' button on notification
7. Observe no functionality at all (notification not dismissed, message not marked as read)

I originally observed this while still on K-9 mail after the Android 15 > 16 update. I switched to Thunderbird and observed the same issue.

Expected behavior

Expectation is that notification actions function regardless of widget presence on Android 16.

Actual behavior

Presence of 'Message List' widget affects the function of notification actions on Android 16.

Logs

No response

Reproduce the failure on Android 16 with and without the Message List widget, using the notification actions described in the issue. Trace the notification-action and widget interaction in the Kotlin Android code; done means Mark as Read and Delete dismiss the notification and perform their actions in both configurations.