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

Conflicts:
- `.github/dependabot.yml`:
  Updated upstream, removed in glitch-soc to disable noise.
  Kept removed.
- `CODE_OF_CONDUCT.md`:
  Upstream updated to a new version of the covenant, but I have not read it
  yet, so kept unchanged.
- `Gemfile.lock`:
  Not a real conflict, one upstream dependency updated textually too close to
  the glitch-soc only `hcaptcha` dependency.
  Applied upstream changes.
- `app/controllers/admin/base_controller.rb`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `app/controllers/application_controller.rb`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `app/controllers/disputes/base_controller.rb`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `app/controllers/relationships_controller.rb`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `app/controllers/statuses_cleanup_controller.rb`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `app/helpers/application_helper.rb`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `app/javascript/mastodon/features/compose/components/compose_form.jsx`:
  Upstream added a highlight animation for onboarding, while we changed the
  max character limit.
  Applied our local changes on top of upstream's new version.
- `app/views/layouts/application.html.haml`:
  Minor conflict due to glitch-soc's theming system.
  Applied upstream changes.
- `stylelint.config.js`:
  Upstream added ignore paths, glitch-soc had extra ignore paths.
  Added the same paths as upstream.

app/controllers/statuses_controller.rb

@@ -6,11 +6,12 @@ class StatusesController < ApplicationController
   include Authorization
   include AccountOwnedConcern
 
+  vary_by -> { public_fetch_mode? ? 'Accept, Accept-Language, Cookie' : 'Accept, Accept-Language, Cookie, Signature' }
+
   before_action :require_account_signature!, only: [:show, :activity], if: -> { request.format == :json && authorized_fetch_mode? }
   before_action :set_status
   before_action :set_instance_presenter
   before_action :redirect_to_original, only: :show
-  before_action :set_cache_headers
   before_action :set_body_classes, only: :embed
 
   after_action :set_link_headers
@@ -29,7 +30,7 @@ class StatusesController < ApplicationController
       end
 
       format.json do
-        expires_in 3.minutes, public: @status.distributable? && public_fetch_mode?
+        expires_in 3.minutes, public: true if @status.distributable? && public_fetch_mode?
         render_with_cache json: @status, content_type: 'application/activity+json', serializer: ActivityPub::NoteSerializer, adapter: ActivityPub::Adapter
       end
     end