diff --git a/config/default.js b/config/default.js
index 673980859a8..be7442489df 100644
--- a/config/default.js
+++ b/config/default.js
@@ -180,14 +180,8 @@ module.exports = {
 
   // Supported languages.
   langs: [
-    'af',
     'ar',
-    'ast',
-    'az',
     'bg',
-    'bn',
-    'bs',
-    'ca',
     'cak',
     'cs',
     'da',
@@ -201,14 +195,10 @@ module.exports = {
     'es-CL',
     'es-ES',
     'es-MX',
-    'et',
-    'eu',
-    'fa',
     'fi',
     'fr',
     'fur',
     'fy-NL',
-    'ga-IE',
     'he',
     'hr',
     'hsb',
@@ -221,12 +211,7 @@ module.exports = {
     'ka',
     'kab',
     'ko',
-    'lt',
-    'lv',
-    'mk',
-    'mn',
     'ms',
-    'mt',
     'nb-NO',
     'nl',
     'nn-NO',
@@ -236,7 +221,6 @@ module.exports = {
     'pt-PT',
     'ro',
     'ru',
-    'si',
     'sk',
     'sl',
     'sq',
@@ -245,7 +229,6 @@ module.exports = {
     'th',
     'tr',
     'uk',
-    'ur',
     'vi',
     'zh-CN',
     'zh-TW',
diff --git a/tests/unit/amo/components/TestAddonTitle.js b/tests/unit/amo/components/TestAddonTitle.js
index 562e1bf01df..846fd4e7896 100644
--- a/tests/unit/amo/components/TestAddonTitle.js
+++ b/tests/unit/amo/components/TestAddonTitle.js
@@ -127,7 +127,7 @@ describe(__filename, () => {
 
   it('handles RTL mode', () => {
     // `fa` is a RTL language.
-    dispatchClientMetadata({ lang: 'fa', store });
+    dispatchClientMetadata({ lang: 'ar', store });
 
     const author1 = {
       ...fakeAddon.authors[0],
@@ -149,9 +149,9 @@ describe(__filename, () => {
 
     expect(screen.getAllByRole('link')).toHaveLength(2);
     const link1 = screen.getByRole('link', { name: author1.name });
-    expect(link1).toHaveAttribute('href', `/fa/android/user/${author1.id}/`);
+    expect(link1).toHaveAttribute('href', `/ar/android/user/${author1.id}/`);
     const link2 = screen.getByRole('link', { name: author2.name });
-    expect(link2).toHaveAttribute('href', `/fa/android/user/${author2.id}/`);
+    expect(link2).toHaveAttribute('href', `/ar/android/user/${author2.id}/`);
 
     expect(screen.getByClassName('AddonTitle-author')).toHaveTextContent(
       `${author1.name} ,${author2.name} by`,
diff --git a/tests/unit/test_localesConfig.js b/tests/unit/test_localesConfig.js
index ae6a9bfc403..16ca4c9ea97 100644
--- a/tests/unit/test_localesConfig.js
+++ b/tests/unit/test_localesConfig.js
@@ -7,6 +7,7 @@ import config from 'config';
 import { globSync } from 'glob';
 
 import { langToLocale, localeToLang } from 'amo/i18n/utils';
+import { unfilteredLanguages } from 'amo/languages';
 
 const langs = config.get('langs');
 const basePath = config.get('basePath');
@@ -18,6 +19,7 @@ describe(__filename, () => {
   it.each(langs)('should have a corresponding %s dir in locale', (lang) => {
     fs.lstatSync(path.join(basePath, 'locale', langToLocale(lang)));
   });
+  const allKnownLanguages = Object.keys(unfilteredLanguages);
 
   for (const localeDir of globSync('locale/*')) {
     const locale = path.basename(localeDir);
@@ -26,8 +28,8 @@ describe(__filename, () => {
       continue;
     }
     // eslint-disable no-loop-func
-    it(`should have a "${lang}" entry for locale dir in config.langs`, () =>
-      expect(langs).toContain(lang));
+    it(`should have a "${lang}" entry in unfilteredLanguages because locale dir exists`, () =>
+      expect(allKnownLanguages).toContain(lang));
   }
 
   describe('Check Locale JS files', () => {