I’d guess, it’s the authtoken cookie, since that has the right kind of expiry date for me and, well, makes sense from an OIDC perspective.
I might see, though, if the suggestion from @AlecSadler@lemmy.dbzer0.com maybe works. The Outlook webpage also redirects to outlook.cloud.microsoft since like, yesterday, which might’ve also unfucked things somehow? At least, I didn’t get the logout loop, when I did try to test Alec’s method just now.































These days, you also likely get faster loading times when you self-host the font, because it can be sent through the same HTTPS connection and because caching doesn’t work anymore like it used to many years ago (cached files aren’t shared anymore between websites).