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?
Web browser
Despite all the other answers, I suspect Web Browser is the most popular. As web apps for email got better, development of desktop clients stalled.
Fast search through a lot mail takes some considerable resources to build, store and search an index, and web-based systems do that really well.
I’ve used about all of them over the years: Pine, Mutt, Thunderbird, Evolution, K-Mail and some others.
I eventually threw in the towel and use web UIs now. Fast, available everywhere and good keyboard support, especially when paired with a browser extension like Vimium.
Web UIs rarely support everything one needs; usually they support their own system and maybe a little bit of bonus.
Outlook web for hosted Exchange won’t even do multiple mailboxes in a unified Inbox, even on the same account!
Right. I’m glad there are options. Despite their flaws, web UIs for email are massively popular.