As someone that gets 100+ emails a day, multi-select is very important and it's probably the most disturbing thing about Proton for me. I can't click CTRL + Left click or SHIFT + Left click to select just like in a usual mail program or file explorer on macOS or Windows.

This additionally to pinned messages (which already has feature requests that I voted for) are probably the most important features for us right now. Thank you very much!