diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index c6d148c8c8..3b2070f39d 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -62,6 +62,7 @@ class ApplicationController < ActionController::Base
       pack: pack_name,
       preload: nil,
       skin: nil,
+      supported_locales: data['locales'],
     }
     if data['pack'][pack_name].is_a?(Hash)
       pack_data[:common] = nil if data['pack'][pack_name]['use_common'] == false
@@ -93,6 +94,7 @@ class ApplicationController < ActionController::Base
       pack: nil,
       preload: nil,
       skin: nil,
+      supported_locales: data['locales'],
     }
   end
 
diff --git a/app/javascript/flavours/glitch/locales/ar.js b/app/javascript/flavours/glitch/locales/ar.js
new file mode 100644
index 0000000000..1081147d5a
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/ar.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/ar.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/bg.js b/app/javascript/flavours/glitch/locales/bg.js
new file mode 100644
index 0000000000..979039376f
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/bg.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/bg.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/ca.js b/app/javascript/flavours/glitch/locales/ca.js
new file mode 100644
index 0000000000..baf76bd6f7
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/ca.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/ca.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/de.js b/app/javascript/flavours/glitch/locales/de.js
new file mode 100644
index 0000000000..ce64536235
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/de.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/de.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/en.js b/app/javascript/flavours/glitch/locales/en.js
new file mode 100644
index 0000000000..1d2e0ecf41
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/en.js
@@ -0,0 +1,50 @@
+import inherited from 'mastodon/locales/en.json';
+
+const messages = {
+  'getting_started.open_source_notice': 'Glitchsoc is free open source software forked from {Mastodon}. You can contribute or report issues on GitHub at {github}.',
+  'layout.auto': 'Auto',
+  'layout.current_is': 'Your current layout is:',
+  'layout.desktop': 'Desktop',
+  'layout.mobile': 'Mobile',
+  'navigation_bar.app_settings': 'App settings',
+  'getting_started.onboarding': 'Show me around',
+  'onboarding.page_one.federation': '{domain} is an \'instance\' of Mastodon. Mastodon is a network of independent servers joining up to make one larger social network. We call these servers instances.',
+  'onboarding.page_one.welcome': 'Welcome to {domain}!',
+  'onboarding.page_six.github': '{domain} runs on Glitchsoc. Glitchsoc is a friendly {fork} of {Mastodon}, and is compatible with any Mastodon instance or app. Glitchsoc is entirely free and open-source. You can report bugs, request features, or contribute to the code on {github}.',
+  'settings.auto_collapse': 'Automatic collapsing',
+  'settings.auto_collapse_all': 'Everything',
+  'settings.auto_collapse_lengthy': 'Lengthy toots',
+  'settings.auto_collapse_media': 'Toots with media',
+  'settings.auto_collapse_notifications': 'Notifications',
+  'settings.auto_collapse_reblogs': 'Boosts',
+  'settings.auto_collapse_replies': 'Replies',
+  'settings.close': 'Close',
+  'settings.collapsed_statuses': 'Collapsed toots',
+  'settings.enable_collapsed': 'Enable collapsed toots',
+  'settings.general': 'General',
+  'settings.image_backgrounds': 'Image backgrounds',
+  'settings.image_backgrounds_media': 'Preview collapsed toot media',
+  'settings.image_backgrounds_users': 'Give collapsed toots an image background',
+  'settings.media': 'Media',
+  'settings.media_letterbox': 'Letterbox media',
+  'settings.media_fullwidth': 'Full-width media previews',
+  'settings.preferences': 'User preferences',
+  'settings.wide_view': 'Wide view (Desktop mode only)',
+  'settings.navbar_under': 'Navbar at the bottom (Mobile only)',
+  'status.collapse': 'Collapse',
+  'status.uncollapse': 'Uncollapse',
+
+  'home.column_settings.show_direct': 'Show DMs',
+
+  'notification.markForDeletion': 'Mark for deletion',
+  'notifications.clear': 'Clear all my notifications',
+  'notifications.marked_clear_confirmation': 'Are you sure you want to permanently clear all selected notifications?',
+  'notifications.marked_clear': 'Clear selected notifications',
+
+  'notification_purge.btn_all': 'Select\nall',
+  'notification_purge.btn_none': 'Select\nnone',
+  'notification_purge.btn_invert': 'Invert\nselection',
+  'notification_purge.btn_apply': 'Clear\nselected',
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/eo.js b/app/javascript/flavours/glitch/locales/eo.js
new file mode 100644
index 0000000000..04192f5064
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/eo.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/eo.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/es.js b/app/javascript/flavours/glitch/locales/es.js
new file mode 100644
index 0000000000..456df3c47e
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/es.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/es.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/fa.js b/app/javascript/flavours/glitch/locales/fa.js
new file mode 100644
index 0000000000..d82461a1a2
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/fa.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/fa.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/fi.js b/app/javascript/flavours/glitch/locales/fi.js
new file mode 100644
index 0000000000..11c3cd082f
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/fi.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/fi.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/fr.js b/app/javascript/flavours/glitch/locales/fr.js
new file mode 100644
index 0000000000..8562f55944
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/fr.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/fr.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/he.js b/app/javascript/flavours/glitch/locales/he.js
new file mode 100644
index 0000000000..99516ee0cf
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/he.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/he.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/hr.js b/app/javascript/flavours/glitch/locales/hr.js
new file mode 100644
index 0000000000..dbf9b4b9fb
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/hr.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/hr.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/hu.js b/app/javascript/flavours/glitch/locales/hu.js
new file mode 100644
index 0000000000..1f0849af3c
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/hu.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/hu.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/id.js b/app/javascript/flavours/glitch/locales/id.js
new file mode 100644
index 0000000000..07e5f7e56a
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/id.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/id.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/io.js b/app/javascript/flavours/glitch/locales/io.js
new file mode 100644
index 0000000000..74ea6fae6c
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/io.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/io.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/it.js b/app/javascript/flavours/glitch/locales/it.js
new file mode 100644
index 0000000000..90f5430932
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/it.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/it.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/glitch/locales/ja.json b/app/javascript/flavours/glitch/locales/ja.js
similarity index 96%
rename from app/javascript/glitch/locales/ja.json
rename to app/javascript/flavours/glitch/locales/ja.js
index a84b4cbe96..98b6a696f0 100644
--- a/app/javascript/glitch/locales/ja.json
+++ b/app/javascript/flavours/glitch/locales/ja.js
@@ -1,4 +1,6 @@
-{
+import inherited from 'mastodon/locales/ja.json';
+
+const messages = {
   "getting_started.open_source_notice": "Glitchsocは{Mastodon}によるフリーなオープンソースソフトウェアです。誰でもGitHub（{github}）から開発に參加したり、問題を報告したりできます。",
   "layout.auto": "自動",
   "layout.current_is": "あなたの現在のレイアウト:",
@@ -44,4 +46,6 @@
   "notification_purge.btn_none": "選択\n解除",
   "notification_purge.btn_invert": "選択を\n反転",
   "notification_purge.btn_apply": "選択したものを\n削除"
-}
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/ko.js b/app/javascript/flavours/glitch/locales/ko.js
new file mode 100644
index 0000000000..3b55f89b93
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/ko.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/ko.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/nl.js b/app/javascript/flavours/glitch/locales/nl.js
new file mode 100644
index 0000000000..17c371c58f
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/nl.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/nl.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/no.js b/app/javascript/flavours/glitch/locales/no.js
new file mode 100644
index 0000000000..794b1da25a
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/no.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/no.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/oc.js b/app/javascript/flavours/glitch/locales/oc.js
new file mode 100644
index 0000000000..8f161fd8c1
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/oc.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/oc.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/pl.js b/app/javascript/flavours/glitch/locales/pl.js
new file mode 100644
index 0000000000..818436710a
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/pl.js
@@ -0,0 +1,48 @@
+import inherited from 'mastodon/locales/pl.json';
+
+const messages = {
+  'getting_started.open_source_notice': 'Glitchsoc jest wolnym i otwartoźródłowym forkiem oprogramowania {Mastodon}. Możesz współtworzyć projekt lub zgłaszać błędy na GitHubie pod adresem {github}.',
+  'layout.auto': 'Automatyczny',
+  'layout.current_is': 'Twój obecny układ to:',
+  'layout.desktop': 'Desktopowy',
+  'layout.mobile': 'Mobilny',
+  'navigation_bar.app_settings': 'Ustawienia aplikacji',
+  'getting_started.onboarding': 'Rozejrzyj się',
+  'onboarding.page_one.federation': '{domain} jest \'instancją\' Mastodona. Mastodon to sieć działających niezależnie serwerów tworzących jedną sieć społecznościową. Te serwery nazywane są instancjami.',
+  'onboarding.page_one.welcome': 'Witamy na {domain}!',
+  'onboarding.page_six.github': '{domain} jest oparty na Glitchsoc. Glitchsoc jest {forkiem} {Mastodon}a kompatybilnym z każdym klientem i aplikacją Mastodona. Glitchsoc jest całkowicie wolnym i otwartoźródłowym oprogramowaniem. Możesz zgłaszać błędy i sugestie funkcji oraz współtworzyć projekt na {github}.',
+  'settings.auto_collapse': 'Automatyczne zwijanie',
+  'settings.auto_collapse_all': 'Wszystko',
+  'settings.auto_collapse_lengthy': 'Długie wpisy',
+  'settings.auto_collapse_media': 'Wpisy z zawartością multimedialną',
+  'settings.auto_collapse_notifications': 'Powiadomienia',
+  'settings.auto_collapse_reblogs': 'Podbicia',
+  'settings.auto_collapse_replies': 'Odpowiedzi',
+  'settings.close': 'Zamknij',
+  'settings.collapsed_statuses': 'Zwijanie wpisów',
+  'settings.enable_collapsed': 'Włącz zwijanie wpisów',
+  'settings.general': 'Ogólne',
+  'settings.image_backgrounds': 'Obrazy w tle',
+  'settings.image_backgrounds_media': 'Wyświetlaj zawartość multimedialną zwiniętych wpisów',
+  'settings.image_backgrounds_users': 'Nadaj tło zwiniętym wpisom',
+  'settings.media': 'Zawartość multimedialna',
+  'settings.media_letterbox': 'Letterbox media',
+  'settings.media_fullwidth': 'Podgląd zawartości multimedialnej o pełnej szerokości',
+  'settings.preferences': 'Preferencje użyytkownika',
+  'settings.wide_view': 'Szeroki widok (tylko w trybie desktopowym)',
+  'settings.navbar_under': 'Pasek nawigacji na dole (tylko w trybie mobilnym)',
+  'status.collapse': 'Zwiń',
+  'status.uncollapse': 'Rozwiń',
+
+  'notification.markForDeletion': 'Oznacz do usunięcia',
+  'notifications.clear': 'Wyczyść wszystkie powiadomienia',
+  'notifications.marked_clear_confirmation': 'Czy na pewno chcesz bezpowrtonie usunąć wszystkie powiadomienia?',
+  'notifications.marked_clear': 'Usuń zaznaczone powiadomienia',
+
+  'notification_purge.btn_all': 'Zaznacz\nwszystkie',
+  'notification_purge.btn_none': 'Odznacz\nwszystkie',
+  'notification_purge.btn_invert': 'Odwróć\nzaznaczenie',
+  'notification_purge.btn_apply': 'Usuń\nzaznaczone',
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/pt-BR.js b/app/javascript/flavours/glitch/locales/pt-BR.js
new file mode 100644
index 0000000000..6fed635f8f
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/pt-BR.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/pt-BR.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/pt.js b/app/javascript/flavours/glitch/locales/pt.js
new file mode 100644
index 0000000000..0156f55ff2
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/pt.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/pt.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/ru.js b/app/javascript/flavours/glitch/locales/ru.js
new file mode 100644
index 0000000000..0e9f1de717
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/ru.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/ru.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/sv.js b/app/javascript/flavours/glitch/locales/sv.js
new file mode 100644
index 0000000000..b62c353fe4
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/sv.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/sv.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/th.js b/app/javascript/flavours/glitch/locales/th.js
new file mode 100644
index 0000000000..e939f86312
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/th.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/th.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/tr.js b/app/javascript/flavours/glitch/locales/tr.js
new file mode 100644
index 0000000000..c2b740617a
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/tr.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/tr.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/uk.js b/app/javascript/flavours/glitch/locales/uk.js
new file mode 100644
index 0000000000..ab6d9a7dc7
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/uk.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/uk.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/zh-CN.js b/app/javascript/flavours/glitch/locales/zh-CN.js
new file mode 100644
index 0000000000..944588e023
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/zh-CN.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/zh-CN.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/zh-HK.js b/app/javascript/flavours/glitch/locales/zh-HK.js
new file mode 100644
index 0000000000..b71c81f2b3
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/zh-HK.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/zh-HK.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/locales/zh-TW.js b/app/javascript/flavours/glitch/locales/zh-TW.js
new file mode 100644
index 0000000000..de2b7769c9
--- /dev/null
+++ b/app/javascript/flavours/glitch/locales/zh-TW.js
@@ -0,0 +1,7 @@
+import inherited from 'mastodon/locales/zh-TW.json';
+
+const messages = {
+  //  No translations available.
+};
+
+export default Object.assign({}, inherited, messages);
diff --git a/app/javascript/flavours/glitch/names.yml b/app/javascript/flavours/glitch/names.yml
new file mode 100644
index 0000000000..b3d579cb27
--- /dev/null
+++ b/app/javascript/flavours/glitch/names.yml
@@ -0,0 +1,6 @@
+en:
+  flavours:
+    glitch: Glitch Edition
+  skins:
+    glitch:
+      default: Default
diff --git a/app/javascript/flavours/glitch/theme.yml b/app/javascript/flavours/glitch/theme.yml
index fe09fa1055..9437e2c045 100644
--- a/app/javascript/flavours/glitch/theme.yml
+++ b/app/javascript/flavours/glitch/theme.yml
@@ -20,6 +20,12 @@ pack:
   settings:
   share: packs/share.js
 
+#  (OPTIONAL) The directory which contains localization files for
+#  the flavour, relative to this directory. The contents of this
+#  directory must be `.js` or `.json` files whose names correspond to
+#  language tags and whose default exports are a messages object.
+locales: locales
+
 #  (OPTIONAL) The directory which contains the pack files.
 #  Defaults to the theme directory (`app/javascript/themes/[theme]`),
 #  which should be sufficient for like 99% of use-cases lol.
diff --git a/app/javascript/flavours/vanilla/names.yml b/app/javascript/flavours/vanilla/names.yml
new file mode 100644
index 0000000000..8816fcb3ab
--- /dev/null
+++ b/app/javascript/flavours/vanilla/names.yml
@@ -0,0 +1,6 @@
+en:
+  flavours:
+    vanilla: Vanilla Mastodon
+  skins:
+    vanilla:
+      default: Default
diff --git a/app/javascript/flavours/vanilla/theme.yml b/app/javascript/flavours/vanilla/theme.yml
index 67fd9723e8..491ea173b0 100644
--- a/app/javascript/flavours/vanilla/theme.yml
+++ b/app/javascript/flavours/vanilla/theme.yml
@@ -20,13 +20,17 @@ pack:
   settings:
   share: share.js
 
+#  (OPTIONAL) The directory which contains localization files for
+#  the flavour, relative to this directory.
+locales: ../../mastodon/locales
+
 #  (OPTIONAL) The directory which contains the pack files.
-#  Defaults to the theme directory (`app/javascript/themes/[theme]`),
-#  but in the case of the vanilla Mastodon theme the pack files are
+#  Defaults to this directory (`app/javascript/flavour/[flavour]`),
+#  but in the case of the vanilla Mastodon flavour the pack files are
 #  somewhere else.
 pack_directory: app/javascript/packs
 
-#  (OPTIONAL) By default the theme will fallback to the default theme
+#  (OPTIONAL) By default the theme will fallback to the default flavour
 #  if a particular pack is not provided. You can specify different
 #  fallbacks here, or disable fallback behaviours altogether by
 #  specifying a `null` value.
diff --git a/app/javascript/glitch/locales/en.json b/app/javascript/glitch/locales/en.json
deleted file mode 100644
index 0276cb8370..0000000000
--- a/app/javascript/glitch/locales/en.json
+++ /dev/null
@@ -1,46 +0,0 @@
-{
-  "getting_started.open_source_notice": "Glitchsoc is free open source software forked from {Mastodon}. You can contribute or report issues on GitHub at {github}.",
-  "layout.auto": "Auto",
-  "layout.current_is": "Your current layout is:",
-  "layout.desktop": "Desktop",
-  "layout.mobile": "Mobile",
-  "navigation_bar.app_settings": "App settings",
-  "getting_started.onboarding": "Show me around",
-  "onboarding.page_one.federation": "{domain} is an 'instance' of Mastodon. Mastodon is a network of independent servers joining up to make one larger social network. We call these servers instances.",
-  "onboarding.page_one.welcome": "Welcome to {domain}!",
-  "onboarding.page_six.github": "{domain} runs on Glitchsoc. Glitchsoc is a friendly {fork} of {Mastodon}, and is compatible with any Mastodon instance or app. Glitchsoc is entirely free and open-source. You can report bugs, request features, or contribute to the code on {github}.",
-  "settings.auto_collapse": "Automatic collapsing",
-  "settings.auto_collapse_all": "Everything",
-  "settings.auto_collapse_lengthy": "Lengthy toots",
-  "settings.auto_collapse_media": "Toots with media",
-  "settings.auto_collapse_notifications": "Notifications",
-  "settings.auto_collapse_reblogs": "Boosts",
-  "settings.auto_collapse_replies": "Replies",
-  "settings.close": "Close",
-  "settings.collapsed_statuses": "Collapsed toots",
-  "settings.enable_collapsed": "Enable collapsed toots",
-  "settings.general": "General",
-  "settings.image_backgrounds": "Image backgrounds",
-  "settings.image_backgrounds_media": "Preview collapsed toot media",
-  "settings.image_backgrounds_users": "Give collapsed toots an image background",
-  "settings.media": "Media",
-  "settings.media_letterbox": "Letterbox media",
-  "settings.media_fullwidth": "Full-width media previews",
-  "settings.preferences": "User preferences",
-  "settings.wide_view": "Wide view (Desktop mode only)",
-  "settings.navbar_under": "Navbar at the bottom (Mobile only)",
-  "status.collapse": "Collapse",
-  "status.uncollapse": "Uncollapse",
-
-  "home.column_settings.show_direct": "Show DMs",
-
-  "notification.markForDeletion": "Mark for deletion",
-  "notifications.clear": "Clear all my notifications",
-  "notifications.marked_clear_confirmation": "Are you sure you want to permanently clear all selected notifications?",
-  "notifications.marked_clear": "Clear selected notifications",
-
-  "notification_purge.btn_all": "Select\nall",
-  "notification_purge.btn_none": "Select\nnone",
-  "notification_purge.btn_invert": "Invert\nselection",
-  "notification_purge.btn_apply": "Clear\nselected"
-}
diff --git a/app/javascript/glitch/locales/pl.json b/app/javascript/glitch/locales/pl.json
deleted file mode 100644
index 1481b6a2ab..0000000000
--- a/app/javascript/glitch/locales/pl.json
+++ /dev/null
@@ -1,44 +0,0 @@
-{
-  "getting_started.open_source_notice": "Glitchsoc jest wolnym i otwartoźródłowym forkiem oprogramowania {Mastodon}. Możesz współtworzyć projekt lub zgłaszać błędy na GitHubie pod adresem {github}.",
-  "layout.auto": "Automatyczny",
-  "layout.current_is": "Twój obecny układ to:",
-  "layout.desktop": "Desktopowy",
-  "layout.mobile": "Mobilny",
-  "navigation_bar.app_settings": "Ustawienia aplikacji",
-  "getting_started.onboarding": "Rozejrzyj się",
-  "onboarding.page_one.federation": "{domain} jest 'instancją' Mastodona. Mastodon to sieć działających niezależnie serwerów tworzących jedną sieć społecznościową. Te serwery nazywane są instancjami.",
-  "onboarding.page_one.welcome": "Witamy na {domain}!",
-  "onboarding.page_six.github": "{domain} jest oparty na Glitchsoc. Glitchsoc jest {forkiem} {Mastodon}a kompatybilnym z każdym klientem i aplikacją Mastodona. Glitchsoc jest całkowicie wolnym i otwartoźródłowym oprogramowaniem. Możesz zgłaszać błędy i sugestie funkcji oraz współtworzyć projekt na {github}.",
-  "settings.auto_collapse": "Automatyczne zwijanie",
-  "settings.auto_collapse_all": "Wszystko",
-  "settings.auto_collapse_lengthy": "Długie wpisy",
-  "settings.auto_collapse_media": "Wpisy z zawartością multimedialną",
-  "settings.auto_collapse_notifications": "Powiadomienia",
-  "settings.auto_collapse_reblogs": "Podbicia",
-  "settings.auto_collapse_replies": "Odpowiedzi",
-  "settings.close": "Zamknij",
-  "settings.collapsed_statuses": "Zwijanie wpisów",
-  "settings.enable_collapsed": "Włącz zwijanie wpisów",
-  "settings.general": "Ogólne",
-  "settings.image_backgrounds": "Obrazy w tle",
-  "settings.image_backgrounds_media": "Wyświetlaj zawartość multimedialną zwiniętych wpisów",
-  "settings.image_backgrounds_users": "Nadaj tło zwiniętym wpisom",
-  "settings.media": "Zawartość multimedialna",
-  "settings.media_letterbox": "Letterbox media",
-  "settings.media_fullwidth": "Podgląd zawartości multimedialnej o pełnej szerokości",
-  "settings.preferences": "Preferencje użyytkownika",
-  "settings.wide_view": "Szeroki widok (tylko w trybie desktopowym)",
-  "settings.navbar_under": "Pasek nawigacji na dole (tylko w trybie mobilnym)",
-  "status.collapse": "Zwiń",
-  "status.uncollapse": "Rozwiń",
-
-  "notification.markForDeletion": "Oznacz do usunięcia",
-  "notifications.clear": "Wyczyść wszystkie powiadomienia",
-  "notifications.marked_clear_confirmation": "Czy na pewno chcesz bezpowrtonie usunąć wszystkie powiadomienia?",
-  "notifications.marked_clear": "Usuń zaznaczone powiadomienia",
-
-  "notification_purge.btn_all": "Zaznacz\nwszystkie",
-  "notification_purge.btn_none": "Odznacz\nwszystkie",
-  "notification_purge.btn_invert": "Odwróć\nzaznaczenie",
-  "notification_purge.btn_apply": "Usuń\nzaznaczone"
-}
diff --git a/app/javascript/mastodon/locales/locale-data/README.md b/app/javascript/locales/locale-data/README.md
similarity index 100%
rename from app/javascript/mastodon/locales/locale-data/README.md
rename to app/javascript/locales/locale-data/README.md
diff --git a/app/javascript/mastodon/locales/locale-data/oc.js b/app/javascript/locales/locale-data/oc.js
similarity index 100%
rename from app/javascript/mastodon/locales/locale-data/oc.js
rename to app/javascript/locales/locale-data/oc.js
diff --git a/app/javascript/skins/vanilla/win95.scss b/app/javascript/skins/vanilla/win95/common.scss
similarity index 100%
rename from app/javascript/skins/vanilla/win95.scss
rename to app/javascript/skins/vanilla/win95/common.scss
diff --git a/app/javascript/skins/vanilla/win95/names.yml b/app/javascript/skins/vanilla/win95/names.yml
new file mode 100644
index 0000000000..2083084a27
--- /dev/null
+++ b/app/javascript/skins/vanilla/win95/names.yml
@@ -0,0 +1,4 @@
+en:
+  skins:
+    vanilla:
+      win95: Ｍａｓｔｏ95
diff --git a/app/lib/themes.rb b/app/lib/themes.rb
index 863326e2d5..49e9ebbc38 100644
--- a/app/lib/themes.rb
+++ b/app/lib/themes.rb
@@ -15,6 +15,14 @@ class Themes
     Dir.glob(Rails.root.join('app', 'javascript', 'flavours', '*', 'theme.yml')) do |path|
       data = YAML.load_file(path)
       name = File.basename(File.dirname(path))
+      if data['locales']
+        locales = []
+        Dir.glob(File.join(File.dirname(path), data['locales'], '*.{js,json}')) do |locale|
+          localeName = File.basename(locale, File.extname(locale))
+          locales.push(localeName) unless localeName.match(/defaultMessages|whitelist|index/)
+        end
+        data['locales'] = locales
+      end
       if data['pack']
         data['name'] = name
         data['skin'] = { 'default' => [] }
diff --git a/app/views/layouts/application.html.haml b/app/views/layouts/application.html.haml
index 99ae7d90d6..20603678b4 100755
--- a/app/views/layouts/application.html.haml
+++ b/app/views/layouts/application.html.haml
@@ -19,7 +19,11 @@
       = title
 
     = javascript_pack_tag "locales", integrity: true, crossorigin: 'anonymous'
-    = javascript_pack_tag "locale_#{I18n.locale}", integrity: true, crossorigin: 'anonymous'
+    - if @theme
+      - if @theme[:supported_locales].include? I18n.locale.to_s
+        = javascript_pack_tag "locales/#{@theme[:flavour]}/#{I18n.locale}", integrity: true, crossorigin: 'anonymous'
+      - elsif @theme[:supported_locales].include? 'en'
+        = javascript_pack_tag "locales/#{@theme[:flavour]}/en", integrity: true, crossorigin: 'anonymous'
     = csrf_meta_tags
 
     = yield :header_tags
diff --git a/app/views/settings/preferences/show.html.haml b/app/views/settings/preferences/show.html.haml
index 9564c03991..e2e48a6998 100644
--- a/app/views/settings/preferences/show.html.haml
+++ b/app/views/settings/preferences/show.html.haml
@@ -27,8 +27,8 @@
 
   .fields-group
     - if Themes.instance.flavours.size > 1
-      = f.input :setting_flavour, collection: Themes.instance.flavours, label_method: lambda { |flavour| I18n.t("themes.#{flavour}", default: flavour) }, wrapper: :with_label, include_blank: false
-      = f.input :setting_skin, collection: Themes.instance.skins_for(current_flavour), label_method: lambda { |skin| I18n.t("themes.#{current_flavour}.skins.#{skin}", default: skin) }, wrapper: :with_label, include_blank: false
+      = f.input :setting_flavour, collection: Themes.instance.flavours, label_method: lambda { |flavour| I18n.t("flavours.#{flavour}", default: flavour) }, wrapper: :with_label, include_blank: false
+      = f.input :setting_skin, collection: Themes.instance.skins_for(current_flavour), label_method: lambda { |skin| I18n.t("skins.#{current_flavour}.#{skin}", default: skin) }, wrapper: :with_label, include_blank: false
 
     = f.input :setting_unfollow_modal, as: :boolean, wrapper: :with_label
     = f.input :setting_boost_modal, as: :boolean, wrapper: :with_label
diff --git a/config/initializers/locale.rb b/config/initializers/locale.rb
new file mode 100644
index 0000000000..04ed316465
--- /dev/null
+++ b/config/initializers/locale.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+I18n.load_path += Dir[Rails.root.join('app', 'javascript', 'flavours', '*', 'names.{rb,yml}').to_s]
+I18n.load_path += Dir[Rails.root.join('app', 'javascript', 'flavours', '*', 'names', '*.{rb,yml}').to_s]
+I18n.load_path += Dir[Rails.root.join('app', 'javascript', 'skins', '*', '*', 'names.{rb,yml}').to_s]
+I18n.load_path += Dir[Rails.root.join('app', 'javascript', 'skins', '*', '*', 'names', '*.{rb,yml}').to_s]
diff --git a/config/locales/ca.yml b/config/locales/ca.yml
index 357e39e315..05c08c01a8 100644
--- a/config/locales/ca.yml
+++ b/config/locales/ca.yml
@@ -678,8 +678,6 @@ ca:
 
       <p>Originalment adaptat a la <a href="https://github.com/discourse/discourse">política de privadesa del Discurs</a>.</p>
     title: "%{instance} Condicions del servei i política de privadesa"
-  themes:
-    default: Mastodont
   time:
     formats:
       default: "%b %d, %Y, %H:%M"
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 0ca320e1ac..c8acc237ac 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -687,8 +687,6 @@ en:
 
       <p>Originally adapted from the <a href="https://github.com/discourse/discourse">Discourse privacy policy</a>.</p>
     title: "%{instance} Terms of Service and Privacy Policy"
-  themes:
-    default: Mastodon
   time:
     formats:
       default: "%b %d, %Y, %H:%M"
diff --git a/config/locales/es.yml b/config/locales/es.yml
index 18b93b08e1..d9084787dc 100644
--- a/config/locales/es.yml
+++ b/config/locales/es.yml
@@ -678,8 +678,6 @@ es:
 
       <p>Adaptado originalmente del <a href="https://github.com/discourse/discourse">discurso de las políticas de privacidad</a>.</p>
     title: Términos del Servicio y Políticas de Privacidad de %{instance}
-  themes:
-    default: Mastodon
   time:
     formats:
       default: "%d de %b del %Y, %H:%M"
diff --git a/config/locales/fr.yml b/config/locales/fr.yml
index cd97f59673..45243d07e5 100644
--- a/config/locales/fr.yml
+++ b/config/locales/fr.yml
@@ -677,8 +677,6 @@ fr:
 
       <p>Originellement adapté à partir de la politique de confidentialité de <a href="https://github.com/discourse/discourse">Discourse</a>.</p>
     title: "%{instance} Conditions d’utilisations et politique de confidentialité"
-  themes:
-    default: Mastodon
   time:
     formats:
       default: "%d %b %Y, %H:%M"
diff --git a/config/locales/pl.yml b/config/locales/pl.yml
index baa26f1dc6..582a2cd03a 100644
--- a/config/locales/pl.yml
+++ b/config/locales/pl.yml
@@ -693,8 +693,6 @@ pl:
 
       <p>Tekst bazuje na <a href="https://github.com/discourse/discourse">polityce prywatności Discourse</a>.</p>
     title: Zasady korzystania i polityka prywatności %{instance}
-  themes:
-    default: Mastodon
   time:
     formats:
       default: "%b %d, %Y, %H:%M"
diff --git a/config/webpack/configuration.js b/config/webpack/configuration.js
index 9cdd6f9345..852185eb98 100644
--- a/config/webpack/configuration.js
+++ b/config/webpack/configuration.js
@@ -30,6 +30,9 @@ for (let i = 0; i < flavourFiles.length; i++) {
   if (!data.pack_directory) {
     data.pack_directory = dirname(flavourFile);
   }
+  if (data.locales) {
+    data.locales = join(dirname(flavourFile), data.locales);
+  }
   if (data.pack && typeof data.pack === 'object') {
     flavours[data.name] = data;
   }
@@ -45,7 +48,7 @@ for (let i = 0; i < skinFiles.length; i++) {
   const data = flavours[name].skin;
   if (lstatSync(skinFile).isDirectory()) {
     data[skin] = {};
-    const skinPacks = glob.sync(resolve(skinFile, '*.{css,scss}'));
+    const skinPacks = glob.sync(join(skinFile, '*.{css,scss}'));
     for (let j = 0; j < skinPacks.length; j++) {
       const pack = skinPacks[i];
       data[skin][basename(pack, extname(pack))] = pack;
diff --git a/config/webpack/generateLocalePacks.js b/config/webpack/generateLocalePacks.js
index a943589f74..09fba4a18c 100644
--- a/config/webpack/generateLocalePacks.js
+++ b/config/webpack/generateLocalePacks.js
@@ -1,70 +1,66 @@
+// A message from upstream:
+// ========================
 // To avoid adding a lot of boilerplate, locale packs are
 // automatically generated here. These are written into the tmp/
 // directory and then used to generate locale_en.js, locale_fr.js, etc.
 
-const fs = require('fs');
-const path = require('path');
+// Glitch note:
+// ============
+// This code has been entirely rewritten to support glitch flavours.
+// However, the underlying process is exactly the same.
+
+const { existsSync, readdirSync, writeFileSync } = require('fs');
+const { join, resolve } = require('path');
 const rimraf = require('rimraf');
 const mkdirp = require('mkdirp');
+const { flavours } = require('./configuration.js');
 
-const localesJsonPath = path.join(__dirname, '../../app/javascript/mastodon/locales');
-const locales = fs.readdirSync(localesJsonPath).filter(filename => {
-  return /\.json$/.test(filename) &&
-    !/defaultMessages/.test(filename) &&
-    !/whitelist/.test(filename);
-}).map(filename => filename.replace(/\.json$/, ''));
-
-const outPath = path.join(__dirname, '../../tmp/packs');
-
-rimraf.sync(outPath);
-mkdirp.sync(outPath);
-
-const outPaths = [];
-
-locales.forEach(locale => {
-  const localePath = path.join(outPath, `locale_${locale}.js`);
-  const baseLocale = locale.split('-')[0]; // e.g. 'zh-TW' -> 'zh'
-  const localeDataPath = [
-    // first try react-intl
-    `../../node_modules/react-intl/locale-data/${baseLocale}.js`,
-    // then check locales/locale-data
-    `../../app/javascript/mastodon/locales/locale-data/${baseLocale}.js`,
-    // fall back to English (this is what react-intl does anyway)
-    '../../node_modules/react-intl/locale-data/en.js',
-  ].filter(filename => fs.existsSync(path.join(outPath, filename)))
-    .map(filename => filename.replace(/..\/..\/node_modules\//, ''))[0];
-
-  let glitchInject = `
-const mergedMessages = messages;
-`;
-
-  const glitchPath = `../../app/javascript/glitch/locales/${locale}.json`;
-  if (fs.existsSync(path.join(outPath, glitchPath))) {
-    glitchInject = `
-import glitchMessages from ${JSON.stringify(glitchPath)};
-
-let mergedMessages = messages;
-Object.keys(glitchMessages).forEach(function (key) {
-   mergedMessages[key] = glitchMessages[key];
-});
-
-`;
+module.exports = Object.keys(flavours).reduce(function (map, entry) {
+  const flavour = flavours[entry];
+  if (!flavour.locales) {
+    return map;
   }
+  const locales = readdirSync(flavour.locales).filter(
+    filename => /\.js(?:on)?$/.test(filename) && !/defaultMessages|whitelist|index/.test(filename)
+  );
+  const outPath = resolve('tmp', 'locales', entry);
+
+  rimraf.sync(outPath);
+  mkdirp.sync(outPath);
 
-  const localeContent = `//
-// locale_${locale}.js
+  locales.forEach(function (locale) {
+    const localeName = locale.replace(/\.js(?:on)?$/, '');
+    const localePath = join(outPath, `${localeName}.js`);
+    const baseLocale = localeName.split('-')[0]; // e.g. 'zh-TW' -> 'zh'
+    const localeDataPath = [
+      // first try react-intl
+      `node_modules/react-intl/locale-data/${baseLocale}.js`,
+      // then check locales/locale-data
+      `app/javascript/locales/locale-data/${baseLocale}.js`,
+      // fall back to English (this is what react-intl does anyway)
+      'node_modules/react-intl/locale-data/en.js',
+    ].filter(
+      filename => existsSync(filename)
+    ).map(
+      filename => filename.replace(/(?:node_modules|app\/javascript)\//, '')
+    )[0];
+    const localeContent = `//
+// locales/${entry}/${localeName}.js
 // automatically generated by generateLocalePacks.js
 //
-import messages from '../../app/javascript/mastodon/locales/${locale}.json';
-import localeData from ${JSON.stringify(localeDataPath)};
-import { setLocale } from 'locales';
-${glitchInject}
-setLocale({messages: mergedMessages, localeData: localeData});
-`;
-  fs.writeFileSync(localePath, localeContent, 'utf8');
-  outPaths.push(localePath);
-});
 
-module.exports = outPaths;
+import messages from '../../../${flavour.locales}/${locale.replace(/\.js$/, '')}';
+import localeData from '${localeDataPath}';
+import { setLocale } from 'locales';
 
+setLocale({
+  localeData,
+  messages,
+});
+`;
+    writeFileSync(localePath, localeContent, 'utf8');
+    map[`locales/${entry}/${localeName}`] = localePath;
+  });
 
+  return map;
+}, {});
diff --git a/config/webpack/shared.js b/config/webpack/shared.js
index e4b057ffbd..35b9bbd1cd 100644
--- a/config/webpack/shared.js
+++ b/config/webpack/shared.js
@@ -1,13 +1,12 @@
 // Note: You must restart bin/webpack-dev-server for changes to take effect
 
 const webpack = require('webpack');
-const { basename, join, resolve } = require('path');
+const { join, resolve } = require('path');
 const { sync } = require('glob');
 const ExtractTextPlugin = require('extract-text-webpack-plugin');
 const ManifestPlugin = require('webpack-manifest-plugin');
-const extname = require('path-complete-extname');
 const { env, settings, core, flavours, output, loadersDir } = require('./configuration.js');
-const localePackPaths = require('./generateLocalePacks');
+const localePacks = require('./generateLocalePacks');
 
 function reducePacks (data, into = {}) {
   if (!data.pack) {
@@ -48,11 +47,7 @@ function reducePacks (data, into = {}) {
 module.exports = {
   entry: Object.assign(
     { locales: resolve('app', 'javascript', 'locales') },
-    localePackPaths.reduce((map, entry) => {
-      const localMap = map;
-      localMap[basename(entry, extname(entry, extname(entry)))] = resolve(entry);
-      return localMap;
-    }, {}),
+    localePacks,
     reducePacks(core),
     Object.keys(flavours).reduce((map, entry) => reducePacks(flavours[entry], map), {})
   ),