I don’t have an answer. This issue is why I left Proton mail. I’m waiting for a built in (or reasonably automatic) solution before migrating my email back to Proton.
Thank you for asking here. I’ll be reading along in case someone has something that’s not too burdensome.
Thanks! I was just thinking “this feels like the IT Crowd”, but I couldn’t remember specifically.
Edit: Also, cool relevant article!