Merge commit '284b46fee7ad682b52c99d0455a1134e1d4e3fc3' into glitch-soc/merge-upstream

Conflicts:
- `app/helpers/theme_helper.rb`:
  Upstream added an experimental feature flag to try out theme refactors.
  Glitch-soc's theming system is too different, so skips the new feature flag.
- `stylelint.config.js`:
  Ditto.

app/javascript/styles/mastodon/admin.scss

@@ -1040,10 +1040,6 @@ a.name-tag,
   margin-top: 15px;
 }
 
-.user-role {
-  color: var(--user-role-accent);
-}
-
 .applications-list {
   .icon {
     vertical-align: middle;