Hello Everyone!
It seems the issue has been resolved.
It seems an update that was applied affected all browsers except IE. They reverted the update, and it all seems to be back to normal 🙂
Here's additional info if you want the technical aspect of it:
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Title:
All users can't open custom PowerApps forms for SharePoint Online in most browsers User Impact: Users may have been unable to open custom PowerApps forms for SharePoint Online.
More info:
Users may have also been unable to open, edit or add new items in lists that contain forms customized in PowerApps. Final status: We've reverted the problematic update, and resources validated that impact was mitigated.
Scope of impact:
Impact was specific to users attempting to open the affected forms from browsers other than Internet Explorer. Start time: Thursday, May 7, 2020, 10:19 AM (3:19 PM UTC) End time: Thursday, May 7, 2020, 12:30 PM (5:30 PM UTC)
Root cause:
A recent service update was causing issues with opening custom PowerApps forms in SharePoint Online. Next steps: - We're reviewing the update to identify how impact was missed during testing to better prevent future recurrences. This is the final update for the event.