[drdaeman]

Apple’s stock apps on macOS (it’s pretty good, fast, stable, has almost all the features I need) and iOS (sucks but I haven’t found anything better), Thunderbird on Windows and GNU/Linux (sucks badly in terms of performance, but everything else is much worse in some regard).

Rainloop for the web, but I almost never use it - it’s a backup option for me, I’m mostly hosting it for friends and family.

[catherd]

We use Rainloop and the 2 biggest issues are almost nonexistent address auto-complete (it will only try to pull addresses from contacts, which nobody bothers setting up any more), and no support for .ics/calendar invites. Have you found a usable solution for either of those?