Merge branch 'main' into glitch-soc/merge-upstream

Conflicts:
- `app/views/admin/announcements/edit.html.haml`:
  Upstream change too close to theming-related glitch-soc change.
  Ported upstream changes.
- `app/views/admin/announcements/new.html.haml`
  Upstream change too close to theming-related glitch-soc change.
  Ported upstream changes.

app/models/media_attachment.rb

@@ -82,6 +82,7 @@ class MediaAttachment < ApplicationRecord
   IMAGE_CONVERTED_STYLES = {
     original: {
       format: 'jpeg',
+      content_type: 'image/jpeg',
     }.merge(IMAGE_STYLES[:original]).freeze,
 
     small: {