System notifications for Microsoft Outlook Web application (OWA) are very inconsistently working.
I found an older thread here,
and have followed the recommended action, which is to turn ON the “Use Google services for push messaging” setting.
This has only partially worked for me. It is still very inconsistent. The system notifications only come through some of the time. And even when they do, there is often a 1-2 minute delay.
I have found this is consistent for both free/consumer Microsoft accounts, and Microsoft 365 accounts.
System notifications work 100% of the time when using OWA in both Chrome and Firefox.