Recent Edge update attempts to sign-in to a profile every time a link is pressed from Outlook

We have found a workaround!
As mentioned, we never used profiles and haven't set up any policies regarding this, besides an RestrictSigninToPattern pointing to a non-existent domain, which we pushed when we switched to Edge from Chrome a year or two ago.

However, today we've set up the BrowserSignin(to 0) policy which has fixed the issue to the point where the users are no longer met with the popup at all when clicking a link from Outlook.

While we still blame the recent update for changing the behavior, considering we haven't touched any policies or settings in months, enabling this policy works for us, at least for now.

In the future however, we would prefer such changes are better communicated in the release notes so we can prepare. The issue can be closed for now.