Currently it's possible to select/copy only a single message, it would be nice to allow selecting multiple messages to allow copy-paste of a conversation, vaguely similarly to what you get if you use "regular" browser selection in the Slack web client:

Matteo Italia  11:05 AM
that would be nice, it's deeply ingrained muscolar memory at least for me, and it works in pretty much every tabbed application I use
11:05
maybe on Mac it's Cmd+Page Down?
cancel  11:05 AM
well, nothing else is using that shortcut on windows, so it should be safe to use
11:05
nope, nothing on that
Matteo Italia  11:05 AM
KDE uses it
11:05
tried right now in Dolphin
cancel  11:06 AM
ok

(of course it may be formatted a bit better)

Yes, this is being worked on. Related to this ticket