7612090ebe
Longer term we should move this tracking fully to nsAlertsService, but given that: * currently it's different how each alert backend tracks notification (e.g. only Windows has IsPrivate() and macOS has separate lists for pending/active alerts) * consolidating that would probably require bigger changes it would be nice to first centralize how the teardown step is triggered and then try consolidating further. (See also bug 1953657.) Differential Revision: https://phabricator.services.mozilla.com/D241477