Merge commit '7530f06deea63a03e0ca05f777f0f1582372c305' into glitch-soc/merge-upstream

Conflicts:
- `app/views/settings/preferences/appearance/show.html.haml`:
  Upstream reorganized the whole page, while glitch-soc had an extra setting.
  Adopted upstream's redesign and moved the extra setting where it made sense.

app/javascript/styles/mastodon/admin.scss

@@ -300,9 +300,9 @@ $content-width: 840px;
       font-size: 13px;
       font-weight: 700;
       color: $darker-text-color;
-      padding-bottom: 8px;
+      padding-top: 24px;
       margin-bottom: 8px;
-      border-bottom: 1px solid var(--background-border-color);
+      border-top: 1px solid var(--background-border-color);
     }
 
     h6 {