Persistent notification sometimes does not clear

🐞 Bug Report

Reproduction steps

Can consistently reproduce by:

1. Open app
2. Bootstrap
3. Open tab/website
4. Background app
5. Wait for "Close private tabs" notification to appear
6. Wait roughly 5 additional seconds
7. Close app by swiping it away from the recent items screen
8. Notice the notification goes away for about a second, but then comes back
9. At this point the notification is in a sort of zombie state where no matter how many times you swipe it away, it will stick around until the app crashes or is force stopped.

Video showing the above steps to reproduce the persistent notification bug

Bookkeeping

• Browser channel:
  • Release
  • Alpha
  • Nightly
• Operating System:
  • Windows
  • macOS
  • Linux
  • Android
  • Tails
  • Other (please specify):

Does this bug occur in a fresh installation?

Yes

Is this bug new? If it is a regression, in which version of the browser did this bug first appear?

Not new

Does this bug occur in the Alpha release channel?

Yes

Does this bug occur in Firefox Rapid Release?

No

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