In Windows 10 and Windows 11, when you log into an app (e.g. Teams) with your Microsoft Online account, you might get a pop-up:

Stay signed in to all your apps

You will have a big OK button to accept this or a small link saying "No, sign in to this app only". If you click on the OK button, all Apps that use a Microsoft Online account will now be logged in with the account. In addition, Windows tries to do a Workplace Join to Azure. So in most cases, clicking OK does more bad than good.

To prevent this pop-up and and also to disable the automatic workplace join, set the following Registry key:

HKLM\SOFTWARE\Policies\Microsoft\Windows\WorkplaceJoin BlockAADWorkplaceJoin = dword:00000001