Clicking on a notification has no effect if background script is suspended

[aecreations]

Clippings 7.0rc4

In version 7.0, Clippings was migrated to MV3, which means that the background script is suspended after a period of inactivity. But it was observed that when clicking on a notification while the extension is suspended, nothing happens.

This is causing problems for notifications:

• Clicking on the backup reminder notification is supposed to open Clippings Manager. For first-run, it opens the Backup dialog
• Clicking on the What's New notification that appears after an upgrade is supposed to open the What's New page in a new browser tab
• Clicking on the Sync Clippings Helper update notification is supposed to open the AE Creations website in a new browser tab

This issue is most likely to occur if the user didn't click on the notification as soon as it popped up - at that point, the background script would still be running since it had just triggered the notification, and therefore can respond to click events from the notification. But although notifications disappear after a few seconds, they are still accessible for viewing later - on Windows, recent notifications appear in the Action Center, and macOS has a sidebar that appears when clicking on the date and time on the right-hand side of the desktop menu bar.

[aecreations]

Bug entered in Bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1932263