Merge commit 'a0ce77673c977e3a90d0c7d1c2acd250b7fad0c2' into glitch-soc/merge-upstream

Conflicts:
- `app/controllers/application_controller.rb`:
  Upstream added an experimental color and contrast theme control.
  Conflicts because of glitch-soc's different theming system.
  Adapted upstream's changes.
- `app/views/layouts/application.html.haml`:
  Upstream added an experimental color and contrast theme control.
  Conflicts because of glitch-soc's different theming system.
  Adapted upstream's changes.
- `app/views/settings/preferences/appearance/show.html.haml`:
  Upstream added an experimental color and contrast theme control.
  Conflicts because of glitch-soc's different theming system.
  Adapted upstream's changes.

app/javascript/styles/mastodon/forms.scss

@@ -716,6 +716,17 @@ code {
     }
   }
 
+  .horizontal-options .label_input__wrapper {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 20px;
+
+    .radio,
+    .radio > label {
+      margin-bottom: 0;
+    }
+  }
+
   .status-card {
     contain: unset;
   }