Should this be capitalized to match the capitalized "t" in the old version of the code? In my opinion, the lowercase 'chat' looks nicer but wanted to confirm.

1. Actually, in this rare case we are already using the correct term! "Promote" is something that applies to sidebars, which we are calling "threads" going forward.
2. On native we use "Promote to channel", I think. Should we consider using the same language here?

Same comment as above – consider "Promote to channel" for consistency with native

Let's say "Promoting a sidebar to a channel cannot be undone."

(I assume sidebar -> thread will be handled in a separate diff)

Same comment as above – consider "Promote to channel" for consistency with native

I agree that lowercase is better here

Let's say "channel" instead of "chat", since subchannels can only exist inside another channel (or community, which we can consider a special kind of channel)