@rvtdadmin
Here is the testing for "Office 365 Worldwide" + New Edge browser on Windows 11. I think it is similar to GCC:
Make sure the "Notifications" are enabled for "outlook.office.com" first.
Then enable the "Desktop notifications" from OWA settings (I only enable the notification for emails that sent to Inbox folder):
Here is the result:
Here is detailed information about it: OWA web push notifications
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