I also switched to Fastmail. iirc they are not the best privacy wise as they are based in Australia. They do however have a no-nonsense IMAP connection (unlike Protonmail) and they allow multiple custom domains without extra pay. The IMAP connection however is not available on the lowest tier.

So far I've not regretted the switch, and it also integrates nicely with 1Password masked mails.

Yeah I love this feature. I love it so much that I'll also tell everyone who cares to listen how you can use it. Edit your ~/.config/kitty/kitty.conf file to include map ctrl+c copy_and_clear_or_interrupt and you are good to go. Only issue I have that it doesn't seem to work in the vscode terminal.