A Microsoft file hosting and synchronization service.
It is happening again. In Chrome or Edge (also in private mode). I open onedrive and click on "unlock the personal vault", then I tried different authentication methods like Windows PIN, Send code to email or 2FA App.
Authentication works, but then the popup redirects to an empty page. It looks the same as the screenshot that was posted here.
I also tried it on the phone app, which I never used before. There I get the dialog to set-up the personal vault and enter a 6 digit pin. I did not continue, because I'm afraid of losing the data. The set-up dialog sounded more like creating a new personal vault and not accessing the existing one.