I just can’t find a decent email client that looks like it’s from the last 20 years. Geary and Evolution both appear to be pretty modern but something about using Gmail with a Yubikey just doesn’t work and neither of them will connect to my account. Both on Fedora and OpenSUSE. Thunderbird works but it’s so old fashioned and Betterbird doesn’t look much better. What’s everyone else using?
Agreed on Mailspring, especially if OP wants a modern interface (although I think the new Thunderbird looks fine).
The only thing missing from Mailspring for me is seeing what folders my emails are in when I run a search. Otherwise, it’s the only non-CLI client I’ve found that let’s me use the keyboard to select multiple emails and move them to a folder, something I do in Gmail. If anyone knows of others, let me know! I’ve tried Claws, Evolution, Geary, KMail, and Thunderbird in addition to Mutt and aerc in hopes of finding something to replace Gmail…