I've been overdue in splitting off my personal email from my work email, in part due to dithering over what privacy-respecting paid provider to go with. But I recall Proton and Fastmail looking appealing last time I looked.
Proton seems to now be wandering off into dubious LLM and crypto schemes, so I'm leaning towards Fastmail. If you use it, how's your experience been? Does it work well with Thunderbird and IMAP? Custom domains? How well does it deal with spam? What else should I know?