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

Conflicts:
- README.md
- app/javascript/styles/mastodon/components.scss
  conflicts caused by image URLs being different
- app/models/status.rb
  as_home_timeline removed, kept glitch-soc-only as_direct_timeline
- app/views/statuses/_simple_status.html.haml
- config/locales/en.yml
  some strings were changed upstream
- spec/models/status_spec.rb
  as_home_timeline removed, kept glitch-soc-only as_direct_timeline

app/models/concerns/remotable.rb

@@ -18,7 +18,7 @@ module Remotable
           return
         end
 
-        return if !%w(http https).include?(parsed_url.scheme) || parsed_url.host.blank? || self[attribute_name] == url
+        return if !%w(http https).include?(parsed_url.scheme) || parsed_url.host.blank? || (self[attribute_name] == url && send("#{attachment_name}_file_name").present?)
 
         begin
           Request.new(:get, url).perform do |response|