diff --git a/src/screens/anime/AnimeExtensions.tsx b/src/screens/anime/AnimeExtensions.tsx
index 0dac81c2..91249caa 100644
--- a/src/screens/anime/AnimeExtensions.tsx
+++ b/src/screens/anime/AnimeExtensions.tsx
@@ -11,7 +11,7 @@ import NavbarContext from 'context/NavbarContext';
 import client from 'util/client';
 import useLocalStorage from 'util/useLocalStorage';
 import ExtensionLangSelect from 'components/manga/ExtensionLangSelect';
-import { defualtLangs, langCodeToName, langSortCmp } from 'util/language';
+import { extensionDefaultLangs, langCodeToName, langSortCmp } from 'util/language';
 
 const allLangs: string[] = [];
 
@@ -42,10 +42,6 @@ function groupExtensions(extensions: IExtension[]) {
     return result;
 }
 
-function extensionDefaultLangs() {
-    return [...defualtLangs(), 'all'];
-}
-
 export default function AnimeExtensions() {
     const { setTitle, setAction } = useContext(NavbarContext);
     const [shownLangs, setShownLangs] = useLocalStorage<string[]>('shownExtensionLangs', extensionDefaultLangs());
diff --git a/src/screens/anime/AnimeSources.tsx b/src/screens/anime/AnimeSources.tsx
index 21d2590f..12319b77 100644
--- a/src/screens/anime/AnimeSources.tsx
+++ b/src/screens/anime/AnimeSources.tsx
@@ -10,7 +10,7 @@ import ExtensionLangSelect from 'components/manga/ExtensionLangSelect';
 import SourceCard from 'components/anime/SourceCard';
 import NavbarContext from 'context/NavbarContext';
 import client from 'util/client';
-import { defualtLangs, langCodeToName, langSortCmp } from 'util/language';
+import { sourceDefualtLangs, langCodeToName, langSortCmp } from 'util/language';
 import useLocalStorage from 'util/useLocalStorage';
 
 function sourceToLangList(sources: ISource[]) {
@@ -37,7 +37,7 @@ function groupByLang(sources: ISource[]) {
 export default function AnimeSources() {
     const { setTitle, setAction } = useContext(NavbarContext);
 
-    const [shownLangs, setShownLangs] = useLocalStorage<string[]>('shownSourceLangs', defualtLangs());
+    const [shownLangs, setShownLangs] = useLocalStorage<string[]>('shownSourceLangs', sourceDefualtLangs());
 
     const [sources, setSources] = useState<ISource[]>([]);
     const [fetched, setFetched] = useState<boolean>(false);
diff --git a/src/screens/manga/MangaExtensions.tsx b/src/screens/manga/MangaExtensions.tsx
index afe051cd..c8fc7cad 100644
--- a/src/screens/manga/MangaExtensions.tsx
+++ b/src/screens/manga/MangaExtensions.tsx
@@ -14,7 +14,7 @@ import NavbarContext from 'context/NavbarContext';
 import client from 'util/client';
 import useLocalStorage from 'util/useLocalStorage';
 import ExtensionLangSelect from 'components/manga/ExtensionLangSelect';
-import { defualtLangs, langCodeToName, langSortCmp } from 'util/language';
+import { extensionDefaultLangs, langCodeToName, langSortCmp } from 'util/language';
 import { makeToaster } from 'components/Toast';
 
 const allLangs: string[] = [];
@@ -46,10 +46,6 @@ function groupExtensions(extensions: IExtension[]) {
     return result;
 }
 
-function extensionDefaultLangs() {
-    return [...defualtLangs(), 'all'];
-}
-
 export default function MangaExtensions() {
     const { setTitle, setAction } = useContext(NavbarContext);
     const [shownLangs, setShownLangs] = useLocalStorage<string[]>('shownExtensionLangs', extensionDefaultLangs());
diff --git a/src/screens/manga/MangaSources.tsx b/src/screens/manga/MangaSources.tsx
index 0dc48678..1db560c8 100644
--- a/src/screens/manga/MangaSources.tsx
+++ b/src/screens/manga/MangaSources.tsx
@@ -10,7 +10,9 @@ import ExtensionLangSelect from 'components/manga/ExtensionLangSelect';
 import SourceCard from 'components/manga/SourceCard';
 import NavbarContext from 'context/NavbarContext';
 import client from 'util/client';
-import { defualtLangs, langCodeToName, langSortCmp } from 'util/language';
+import {
+    sourceDefualtLangs, sourceForcedDefaultLangs, langCodeToName, langSortCmp,
+} from 'util/language';
 import useLocalStorage from 'util/useLocalStorage';
 
 function sourceToLangList(sources: ISource[]) {
@@ -37,12 +39,28 @@ function groupByLang(sources: ISource[]) {
 export default function MangaSources() {
     const { setTitle, setAction } = useContext(NavbarContext);
 
-    const [shownLangs, setShownLangs] = useLocalStorage<string[]>('shownSourceLangs', defualtLangs());
+    const [shownLangs, setShownLangs] = useLocalStorage<string[]>('shownSourceLangs', sourceDefualtLangs());
     const [showNsfw] = useLocalStorage<boolean>('showNsfw', true);
 
     const [sources, setSources] = useState<ISource[]>([]);
     const [fetched, setFetched] = useState<boolean>(false);
 
+    useEffect(() => {
+        // make sure all of forcedDefaultLangs() exists in shownLangs
+        sourceForcedDefaultLangs().forEach((forcedLang) => {
+            let hasLang = false;
+            shownLangs.forEach((lang) => {
+                if (lang === forcedLang) hasLang = true;
+            });
+            if (!hasLang) {
+                setShownLangs((shownLangsCopy) => {
+                    shownLangsCopy.push(forcedLang);
+                    return shownLangsCopy;
+                });
+            }
+        });
+    }, [shownLangs]);
+
     useEffect(() => {
         setTitle('Sources');
         setAction(
diff --git a/src/util/language.tsx b/src/util/language.tsx
index 328b0f61..fc85784c 100644
--- a/src/util/language.tsx
+++ b/src/util/language.tsx
@@ -93,11 +93,27 @@ export function langCodeToName(code: string): string {
     return result;
 }
 
-export function defualtLangs() {
+function defaultNativeLang() {
+    return 'en'; // TODO: infer from the browser
+}
+
+export function extensionDefaultLangs() {
     return [
-        // todo: infer this from the browser
-        'en',
-        'localSourceLang',
+        defaultNativeLang(),
+        'all',
+    ];
+}
+
+export function sourceDefualtLangs() {
+    return [
+        defaultNativeLang(),
+        'localsourcelang',
+    ];
+}
+
+export function sourceForcedDefaultLangs(): string[] {
+    return [
+        'localsourcelang',
     ];
 }