Feature Request: Bind installed themes to different groups

[marblewraith]

Describe the solution you'd like

When configuring (Manage Groups → Group Settings), have an additional section with some kinda input element (drop down, fuzzy match text) that lets you select an installed theme for that group.

Is your feature request related to a problem? Please describe.

It's not responding to a problem per se, just an aesthetic enhancement.

If i had to cite a justification (besides being cool) it could help with UX / Accessibility.

Themes are much more visible as compared to tiny icons in the toolbar, and the icon wouldn't need to be pinned for group identification, freeing up toolbar space.