Is your feature request related to a problem? Please describe.
File uploads in an encrypted channel are not encrypted. Only text messages are encrypted. However, since the entire channel is displayed as encrypted, many users will assume that file uploads are also stored encrypted ! To avoid this misunderstanding and the danger that confidential data was uploaded unencrypted, I think it would make sense to warn the user before uploading a file that the upload will not be encrypted.
Describe the solution you’d like
Before uploading a file, warn the user that the file is not encrypted and then mark the file as unencrypted.
Describe alternatives you’ve considered
Disabling file uploads on an encrypted channel is probably not a viable solution, but could be a useful configuration feature of channel/room attributes (disable upload).
This is related to https://github.com/RocketChat/Rocket.Chat/issues/12207