The typing indicator should also change to white to match the texts while in dark mode. The current implementation is almost invisible.
Signal version : 4.64.2
Device : Redmi K20 (Android 10)
Screenshot
There's something wrong. The + Button should be in a much lighter blue than it is in your screenshot. This is how it should look like:

Are you sure you're using Signals Dark Theme and not some phone setting that 'converts' everything to a 'darkmode'?
There's something wrong. The + Button should be in a much lighter blue than it is in your screenshot. This is how it should look like:
Are you sure you're using Signals Dark Theme and not some phone setting that 'converts' everything to a 'darkmode'?
You're right. I turned that off and now it's fine. Sorry for the confusion.
Glad I could help. Have a nice day