SSO, yes I wasn’t sure. Better practice than the outlook client storing login details on their server!
Good point on the replies lol. No matter how much I might try to keep my email provider out of my data, by sending the email to someone else it their email client might share it!
Oh right, if you save your passwords in the Google browser, or your Google phone… They might be stored in Google’s servers in some fashion - to allow you to share them between devices for example. But you do have to enable this functionality (assuming Google isn’t evil).
Well outlook is a complicated one, your credentials absolutely need to be stored in a place your (pop/imap/…) mail server can read from. Else how can they be validated. So if that’s Microsoft, then technically they have your credentials.
Any mail provider that isn’t evil, won’t be able to read your stored credentials until current one way encryption methods are no longer safe
e: in the case of stored/shared browser passwords, I that’s two way encryption… That’s less safe, I recommend not doing so if you can handle the inconvenience.