M365 is doing away with all legacy authentication, do not be surprised if IMAP is completely unusable in the next 12 months. If you simply want to keep a copy of everything, a store and forward SMTP proxy would probably be the solution, so all email going to your domain would hit that first, then send off to M365.
Now that we have 4k HDR displays, tools are starting to popup to accurately emulate the CRT look and feel. 1080p wasn’t enough to catch all the subtle details, but we are finally there. Kinda cool to see the age of CRT never fully died.