I'm not sure what specific issues you've had with mutt, but I have mine setup with multiple accounts & have in the past used it for a work account where I had t

I'm not sure what specific issues you've had with mutt, but I have mine setup with multiple accounts & have in the past used it for a work account where I had to do IMAP/SMTP auth via oauth token rather than username/password. It's definitely not a super well supported happy path & requires some setup, but it's worked well for me. - Multiple accounts: I have a per-account config file with the relevant specifics (https://github.com/wfleming/dotfiles/tree/arch-linux/home/config/mutt/accounts https://github.com/wfleming/dotfiles/tree/arch-linux/home/co...) and use folder hooks to apply those depending on which mailbox I'm viewing (https://github.com/wfleming/dotfiles/blob/arch-linux/home/config/mutt/muttrc#L15-L16 https://github.com/wfleming/dotfiles/blob/arch-linux/home/co...). (Plus a keybinding in each account file to make flipping to the next account easy.) - Non-standard auth: - I use offlineimap to sync my mail, and it supports oauth2 for Gmail. The arch wiki has helpful details: https://wiki.archlinux.org/title/OfflineIMAP#Configuring_OAuth2_and_getting_access_tokens_via_mailctl - For sending mail, I use msmtp, which also supports oauth2. Again, arch wiki has some helpful details. https://wiki.archlinux.org/title/Msmtp#OAuth2_Setup For web & Slack, I sympathize and have toyed with CLI alternatives in the past, but I'm come to terms with the the fact that it's just not that feasible for the most part. Personally, I spend as much time in the terminal as I can, but I've given up on fighting against the tide for everything. The only native apps I usually have open are Firefox, Slack, and Spotify, and that's acceptable to me since it ends up meaning I still spend most of my day in a terminal.