I've been using Office 365 subscription through work on my Mac with Firefox for years. Today, it stopped working. It was actually quite scary: when I logged in, all my information was gone (all email, etc.). When I check Microsoft, it states it supports Firefox for all major OSes except Mac. I can still access Office 365 on Chrome, but I don't like being forced to use a browser I don't like from a company I don't like. IT help through my work has been useless. They just said use Edge.

Does anybody know the status of this change? Is it intended to be permanent or is it a temporary issue? If it's a permanent choice to exclude Mac users from using Firefox, what is the best way to signal protest against this and maybe get Microsoft to rethink making a major, popular browser useless? I would like to support Firefox/Mozilla in pushing back against this potentially significant move to limit their usability. Thanks.