UI: Enable first-party YouTube Chat features in OBS

Unlock the full feature set of the YouTube Chat dock in OBS by removing
custom scripting/CSS logic. Enable the signed-in experience for live
streaming content creators while also sharing login credentials with the
YouTube Control panel dock.

This will allow OBS users to utilize features _already_ supported in the
YouTube Chat plugin, such as

* creating polls
* managing Q&A sessions
* a rich emoji set in the input panel
* emoji fountains
* moderation tools

and many more. These features are available to users who are logged-in
to YouTube Chat and/or the YouTube Control panel.
This commit is contained in:
Internal Server Error - Gitea: Git with a cup of tea
500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f