My workstation that I use almost exclusively is Mint. I am one of those people who are, to put it politely, not keen on Google's ad and data sponge tentacles in every last item on the planet, and so I use Firefox as my primary browser.

O365 has yet to show me many problems with the O365 suite. The only problem I do have is a complete and utter lack of desktop notifications. I'm late to meetings a lot. For someone who values punctuality, it's a major flaw in my view.

We also use Teams a lot, and there the Firefox + Linux story is significantly worse. You lose all teleconference capabilities - and that's true for Chrome or Chromium as well. The chat functionality is acceptable and weirdly, the notifications on Teams work without any problems. Someone on that team needs to show the O365 team how to do it.

I have a VM for when I absolutely have to do something in Windows. For everything else, there's ~~mastercard~~ linux.