Yeah, Protonmail Bridge is my main source of buyer’s remorse wrt. Protonmail. I moved my family e-mail set-up to Protonmail, so I can’t just move away without having to migrate everyone else too. So now I’m just stuck with it. Weird sync issues, random CPU spikes, having to use the web-UI for anything important, etc.
Not sure why they can’t make it work, but I guess trying to make their custom encrypted mail set-up simply doesn’t translate well to IMAP’s weird idiosyncrasies.