diff --git a/packages/docusaurus-theme-classic/codeTranslations/fr.json b/packages/docusaurus-theme-classic/codeTranslations/fr.json
new file mode 100644
index 0000000000..e0a625fe91
--- /dev/null
+++ b/packages/docusaurus-theme-classic/codeTranslations/fr.json
@@ -0,0 +1,18 @@
+{
+  "theme.NotFound.title": "Page introuvable",
+  "theme.NotFound.p1": "Nous n'avons pas trouvé ce que vous recherchez.",
+  "theme.NotFound.p2": "Veuillez contacter le propriétaire du site qui vous a lié à l'URL d'origine et leur faire savoir que leur lien est cassé.",
+  "theme.BlogListPaginator.newerEntries": "Nouvelles entrées",
+  "theme.BlogListPaginator.olderEntries": "Anciennes entrées",
+  "theme.BlogPostItem.readMore": "Lire plus",
+  "theme.BlogPostPaginator.newerPost": "Article plus récent",
+  "theme.BlogPostPaginator.olderPost": "Article plus ancien",
+  "theme.CodeBlock.copied": "Copié",
+  "theme.CodeBlock.copy": "Copier",
+  "theme.DocPaginator.previous": "Précédent",
+  "theme.DocPaginator.next": "Suivant",
+  "theme.EditThisPage.editThisPage": "Éditer cette page",
+  "theme.SkipToContent.skipToMainContent": "Aller au contenu principal",
+  "theme.Playground.liveEditor": "Éditeur en direct",
+  "theme.Playground.result": "Résultat"
+}
diff --git a/packages/docusaurus-theme-classic/src/index.ts b/packages/docusaurus-theme-classic/src/index.ts
index 961582d48d..c35f4086b3 100644
--- a/packages/docusaurus-theme-classic/src/index.ts
+++ b/packages/docusaurus-theme-classic/src/index.ts
@@ -11,6 +11,7 @@ import path from 'path';
 import Module from 'module';
 import postcss from 'postcss';
 import rtlcss from 'rtlcss';
+import {readDefaultCodeTranslationMessages} from '@docusaurus/utils';
 
 const createRequire = Module.createRequire || Module.createRequireFromPath;
 const requireFromDocusaurusCore = createRequire(
@@ -103,6 +104,13 @@ export default function docusaurusThemeClassic(
     getTranslationFiles: async () => getTranslationFiles({themeConfig}),
     translateThemeConfig,
 
+    getDefaultCodeTranslationMessages: () => {
+      return readDefaultCodeTranslationMessages({
+        dirPath: path.resolve(__dirname, '..', 'codeTranslations'),
+        locale: currentLocale,
+      });
+    },
+
     getClientModules() {
       const modules = [
         require.resolve(getInfimaCSSFile(direction)),
diff --git a/packages/docusaurus-types/src/index.d.ts b/packages/docusaurus-types/src/index.d.ts
index 0d784c7d0c..021201e495 100644
--- a/packages/docusaurus-types/src/index.d.ts
+++ b/packages/docusaurus-types/src/index.d.ts
@@ -240,6 +240,12 @@ export interface Plugin<T, U = unknown> {
 
   // translations
   getTranslationFiles?(): Promise<TranslationFiles>;
+  getDefaultCodeTranslationMessages?(): Promise<
+    Record<
+      string, // id
+      string // message
+    >
+  >;
   translateContent?({
     content,
     translationFiles,
diff --git a/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/en.json b/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/en.json
new file mode 100644
index 0000000000..e0bfbb2022
--- /dev/null
+++ b/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/en.json
@@ -0,0 +1,4 @@
+{
+  "id1": "message 1 en",
+  "id2": "message 2 en"
+}
diff --git a/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/fr.json b/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/fr.json
new file mode 100644
index 0000000000..30a174f946
--- /dev/null
+++ b/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/fr.json
@@ -0,0 +1,4 @@
+{
+  "id1": "message 1 fr",
+  "id2": "message 2 fr"
+}
diff --git a/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/fr_FR.json b/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/fr_FR.json
new file mode 100644
index 0000000000..d6b796f4b4
--- /dev/null
+++ b/packages/docusaurus-utils/src/__tests__/__fixtures__/defaultCodeTranslations/fr_FR.json
@@ -0,0 +1,5 @@
+{
+  "id1": "message 1 fr_FR",
+  "id2": "message 2 fr_FR",
+  "id3": "message 3 fr_FR"
+}
diff --git a/packages/docusaurus-utils/src/__tests__/index.test.ts b/packages/docusaurus-utils/src/__tests__/index.test.ts
index 7ad612a0c3..f0ddf80f96 100644
--- a/packages/docusaurus-utils/src/__tests__/index.test.ts
+++ b/packages/docusaurus-utils/src/__tests__/index.test.ts
@@ -6,6 +6,7 @@
  */
 
 import path from 'path';
+import fs from 'fs-extra';
 import {
   fileToPath,
   simpleHash,
@@ -33,6 +34,7 @@ import {
   findFolderContainingFile,
   getFolderContainingFile,
   updateTranslationFileMessages,
+  readDefaultCodeTranslationMessages,
 } from '../index';
 import {sum} from 'lodash';
 
@@ -718,3 +720,89 @@ describe('updateTranslationFileMessages', () => {
     });
   });
 });
+
+describe('readDefaultCodeTranslationMessages', () => {
+  const dirPath = path.resolve(
+    __dirname,
+    '__fixtures__',
+    'defaultCodeTranslations',
+  );
+
+  async function readAsJSON(filename: string) {
+    return JSON.parse(
+      await fs.readFile(path.resolve(dirPath, filename), 'utf8'),
+    );
+  }
+
+  test('for empty locale', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: '',
+        dirPath,
+      }),
+    ).resolves.toEqual({});
+  });
+
+  test('for unexisting locale', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: 'es',
+        dirPath,
+      }),
+    ).resolves.toEqual({});
+  });
+
+  test('for fr but bad folder', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: '',
+        dirPath: __dirname,
+      }),
+    ).resolves.toEqual({});
+  });
+
+  test('for fr', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: 'fr',
+        dirPath,
+      }),
+    ).resolves.toEqual(await readAsJSON('fr.json'));
+  });
+
+  test('for fr_FR', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: 'fr_FR',
+        dirPath,
+      }),
+    ).resolves.toEqual(await readAsJSON('fr_FR.json'));
+  });
+
+  test('for en', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: 'en',
+        dirPath,
+      }),
+    ).resolves.toEqual(await readAsJSON('en.json'));
+  });
+
+  test('for en_US', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: 'en_US',
+        dirPath,
+      }),
+    ).resolves.toEqual(await readAsJSON('en.json'));
+  });
+
+  test('for en_WHATEVER', async () => {
+    await expect(
+      readDefaultCodeTranslationMessages({
+        locale: 'en_WHATEVER',
+        dirPath,
+      }),
+    ).resolves.toEqual(await readAsJSON('en.json'));
+  });
+});
diff --git a/packages/docusaurus-utils/src/index.ts b/packages/docusaurus-utils/src/index.ts
index bcb670bef1..06b5e41d8e 100644
--- a/packages/docusaurus-utils/src/index.ts
+++ b/packages/docusaurus-utils/src/index.ts
@@ -602,3 +602,35 @@ export function updateTranslationFileMessages(
     })),
   };
 }
+
+export async function readDefaultCodeTranslationMessages({
+  dirPath,
+  locale,
+}: {
+  dirPath: string;
+  locale: string;
+}): Promise<Record<string, string>> {
+  const fileNamesToTry = [locale];
+
+  if (locale.includes('_')) {
+    const language = locale.split('_')[0];
+    if (language) {
+      fileNamesToTry.push(language);
+    }
+  }
+
+  // Return the content of the first file that match
+  // fr_FR.json => fr.json => nothing
+  for (const fileName of fileNamesToTry) {
+    const filePath = path.resolve(dirPath, `${fileName}.json`);
+
+    // eslint-disable-next-line no-await-in-loop
+    if (await fs.pathExists(filePath)) {
+      // eslint-disable-next-line no-await-in-loop
+      const fileContent = await fs.readFile(filePath, 'utf8');
+      return JSON.parse(fileContent);
+    }
+  }
+
+  return {};
+}
diff --git a/packages/docusaurus/src/commands/writeTranslations.ts b/packages/docusaurus/src/commands/writeTranslations.ts
index 1c33f11f06..749eaeb0bd 100644
--- a/packages/docusaurus/src/commands/writeTranslations.ts
+++ b/packages/docusaurus/src/commands/writeTranslations.ts
@@ -11,6 +11,8 @@ import {
   writePluginTranslations,
   writeCodeTranslations,
   WriteTranslationsOptions,
+  getPluginsDefaultCodeTranslationMessages,
+  applyDefaultCodeTranslations,
 } from '../server/translations/translations';
 import {extractPluginsSourceCodeTranslations} from '../server/translations/translationsExtractor';
 import {getCustomBabelConfigFilePath, getBabelOptions} from '../webpack/utils';
@@ -47,7 +49,7 @@ export default async function writeTranslations(
   siteDir: string,
   options: WriteTranslationsOptions & {locale?: string},
 ): Promise<void> {
-  const context = await loadContext(siteDir);
+  const context = await loadContext(siteDir, {locale: options.locale});
   const pluginConfigs = loadPluginConfigs(context);
   const plugins = initPlugins({
     pluginConfigs,
@@ -68,10 +70,19 @@ Available locales=[${context.i18n.locales.join(',')}]`,
     isServer: true,
     babelOptions: getCustomBabelConfigFilePath(siteDir),
   });
-  const codeTranslations = await extractPluginsSourceCodeTranslations(
+  const extractedCodeTranslations = await extractPluginsSourceCodeTranslations(
     plugins,
     babelOptions,
   );
+  const defaultCodeMessages = await getPluginsDefaultCodeTranslationMessages(
+    plugins,
+  );
+
+  const codeTranslations = applyDefaultCodeTranslations({
+    extractedCodeTranslations,
+    defaultCodeMessages,
+  });
+
   await writeCodeTranslations({siteDir, locale}, codeTranslations, options);
 
   await Promise.all(
diff --git a/packages/docusaurus/src/server/index.ts b/packages/docusaurus/src/server/index.ts
index 2bba811841..9a5d90b56b 100644
--- a/packages/docusaurus/src/server/index.ts
+++ b/packages/docusaurus/src/server/index.ts
@@ -32,7 +32,10 @@ import {loadHtmlTags} from './html-tags';
 import {getPackageJsonVersion} from './versions';
 import {handleDuplicateRoutes} from './duplicateRoutes';
 import {loadI18n, localizePath} from './i18n';
-import {readCodeTranslationFileContent} from './translations/translations';
+import {
+  readCodeTranslationFileContent,
+  getPluginsDefaultCodeTranslationMessages,
+} from './translations/translations';
 import {mapValues} from 'lodash';
 
 type LoadContextOptions = {
@@ -267,10 +270,15 @@ ${Object.keys(registry)
     JSON.stringify(i18n, null, 2),
   );
 
+  const codeTranslationsWithFallbacks: Record<string, string> = {
+    ...(await getPluginsDefaultCodeTranslationMessages(plugins)),
+    ...codeTranslations,
+  };
+
   const genCodeTranslations = generate(
     generatedFilesDir,
     'codeTranslations.json',
-    JSON.stringify(codeTranslations, null, 2),
+    JSON.stringify(codeTranslationsWithFallbacks, null, 2),
   );
 
   // Version metadata.
diff --git a/packages/docusaurus/src/server/translations/__tests__/translations.test.ts b/packages/docusaurus/src/server/translations/__tests__/translations.test.ts
index 529a913e9c..e18efe3e68 100644
--- a/packages/docusaurus/src/server/translations/__tests__/translations.test.ts
+++ b/packages/docusaurus/src/server/translations/__tests__/translations.test.ts
@@ -12,11 +12,14 @@ import {
   readTranslationFileContent,
   WriteTranslationsOptions,
   localizePluginTranslationFile,
+  getPluginsDefaultCodeTranslationMessages,
+  applyDefaultCodeTranslations,
 } from '../translations';
 import fs from 'fs-extra';
 import tmp from 'tmp-promise';
 import {TranslationFile, TranslationFileContent} from '@docusaurus/types';
 import path from 'path';
+import {InitPlugin} from '../../plugins/init';
 
 async function createTmpSiteDir() {
   const {path: siteDirPath} = await tmp.dir({
@@ -461,3 +464,194 @@ describe('localizePluginTranslationFile', () => {
     });
   });
 });
+
+describe('getPluginsDefaultCodeTranslationMessages', () => {
+  function createTestPlugin(
+    fn: InitPlugin['getDefaultCodeTranslationMessages'],
+  ): InitPlugin {
+    return {getDefaultCodeTranslationMessages: fn} as InitPlugin;
+  }
+
+  test('for empty plugins', async () => {
+    const plugins: InitPlugin[] = [];
+    await expect(
+      getPluginsDefaultCodeTranslationMessages(plugins),
+    ).resolves.toEqual({});
+  });
+
+  test('for 1 plugin without lifecycle', async () => {
+    const plugins: InitPlugin[] = [createTestPlugin(undefined)];
+    await expect(
+      getPluginsDefaultCodeTranslationMessages(plugins),
+    ).resolves.toEqual({});
+  });
+
+  test('for 1 plugin with lifecycle', async () => {
+    const plugins: InitPlugin[] = [
+      createTestPlugin(async () => ({
+        a: '1',
+        b: '2',
+      })),
+    ];
+    await expect(
+      getPluginsDefaultCodeTranslationMessages(plugins),
+    ).resolves.toEqual({
+      a: '1',
+      b: '2',
+    });
+  });
+
+  test('for 2 plugins with lifecycles', async () => {
+    const plugins: InitPlugin[] = [
+      createTestPlugin(async () => ({
+        a: '1',
+        b: '2',
+      })),
+      createTestPlugin(async () => ({
+        c: '3',
+        d: '4',
+      })),
+    ];
+    await expect(
+      getPluginsDefaultCodeTranslationMessages(plugins),
+    ).resolves.toEqual({
+      a: '1',
+      b: '2',
+      c: '3',
+      d: '4',
+    });
+  });
+
+  test('for realistic use-case', async () => {
+    const plugins: InitPlugin[] = [
+      createTestPlugin(undefined),
+      createTestPlugin(async () => ({
+        a: '1',
+        b: '2',
+      })),
+      createTestPlugin(undefined),
+      createTestPlugin(undefined),
+      createTestPlugin(async () => ({
+        a: '2',
+        d: '4',
+      })),
+      createTestPlugin(async () => ({
+        d: '5',
+      })),
+      createTestPlugin(undefined),
+    ];
+    await expect(
+      getPluginsDefaultCodeTranslationMessages(plugins),
+    ).resolves.toEqual({
+      // merge, last plugin wins
+      b: '2',
+      a: '2',
+      d: '5',
+    });
+  });
+});
+
+describe('applyDefaultCodeTranslations', () => {
+  const consoleSpy = jest.spyOn(console, 'warn').mockImplementation() as any;
+  beforeEach(() => {
+    consoleSpy.mockClear();
+  });
+
+  test('for no code and message', () => {
+    expect(
+      applyDefaultCodeTranslations({
+        extractedCodeTranslations: {},
+        defaultCodeMessages: {},
+      }),
+    ).toEqual({});
+    expect(consoleSpy).toHaveBeenCalledTimes(0);
+  });
+
+  test('for code and message', () => {
+    expect(
+      applyDefaultCodeTranslations({
+        extractedCodeTranslations: {
+          id: {
+            message: 'extracted message',
+            description: 'description',
+          },
+        },
+        defaultCodeMessages: {
+          id: 'default message',
+        },
+      }),
+    ).toEqual({
+      id: {
+        message: 'default message',
+        description: 'description',
+      },
+    });
+    expect(consoleSpy).toHaveBeenCalledTimes(0);
+  });
+
+  test('for code and message mismatch', () => {
+    expect(
+      applyDefaultCodeTranslations({
+        extractedCodeTranslations: {
+          id: {
+            message: 'extracted message',
+            description: 'description',
+          },
+        },
+        defaultCodeMessages: {
+          unknownId: 'default message',
+        },
+      }),
+    ).toEqual({
+      id: {
+        message: 'extracted message',
+        description: 'description',
+      },
+    });
+    expect(consoleSpy).toHaveBeenCalledTimes(1);
+    expect(consoleSpy.mock.calls[0][0]).toMatch(/unknownId/);
+  });
+
+  test('for realistic scenario', () => {
+    expect(
+      applyDefaultCodeTranslations({
+        extractedCodeTranslations: {
+          id1: {
+            message: 'extracted message 1',
+            description: 'description 1',
+          },
+          id2: {
+            message: 'extracted message 2',
+            description: 'description 2',
+          },
+          id3: {
+            message: 'extracted message 3',
+            description: 'description 3',
+          },
+        },
+        defaultCodeMessages: {
+          id2: 'default message id2',
+          id3: 'default message id3',
+          idUnknown1: 'default message idUnknown1',
+          idUnknown2: 'default message idUnknown2',
+        },
+      }),
+    ).toEqual({
+      id1: {
+        message: 'extracted message 1',
+        description: 'description 1',
+      },
+      id2: {
+        message: 'default message id2',
+        description: 'description 2',
+      },
+      id3: {
+        message: 'default message id3',
+        description: 'description 3',
+      },
+    });
+    expect(consoleSpy).toHaveBeenCalledTimes(1);
+    expect(consoleSpy.mock.calls[0][0]).toMatch(/idUnknown1/);
+    expect(consoleSpy.mock.calls[0][0]).toMatch(/idUnknown2/);
+  });
+});
diff --git a/packages/docusaurus/src/server/translations/translations.ts b/packages/docusaurus/src/server/translations/translations.ts
index dde540bb7d..dff7e5d6e9 100644
--- a/packages/docusaurus/src/server/translations/translations.ts
+++ b/packages/docusaurus/src/server/translations/translations.ts
@@ -8,7 +8,11 @@ import path from 'path';
 import fs from 'fs-extra';
 import {InitPlugin} from '../plugins/init';
 import {mapValues, difference} from 'lodash';
-import {TranslationFileContent, TranslationFile} from '@docusaurus/types';
+import {
+  TranslationFileContent,
+  TranslationFile,
+  TranslationMessage,
+} from '@docusaurus/types';
 import {getPluginI18nPath, toMessageRelativeFilePath} from '@docusaurus/utils';
 import * as Joi from 'joi';
 import chalk from 'chalk';
@@ -259,3 +263,46 @@ export async function localizePluginTranslationFile({
     return translationFile;
   }
 }
+
+export async function getPluginsDefaultCodeTranslationMessages(
+  plugins: InitPlugin[],
+): Promise<Record<string, string>> {
+  const pluginsMessages = await Promise.all(
+    plugins.map((plugin) => plugin.getDefaultCodeTranslationMessages?.() ?? {}),
+  );
+
+  return pluginsMessages.reduce((allMessages, pluginMessages) => {
+    return {...allMessages, ...pluginMessages};
+  }, {});
+}
+
+export function applyDefaultCodeTranslations({
+  extractedCodeTranslations,
+  defaultCodeMessages,
+}: {
+  extractedCodeTranslations: Record<string, TranslationMessage>;
+  defaultCodeMessages: Record<string, string>;
+}): Record<string, TranslationMessage> {
+  const unusedDefaultCodeMessages = difference(
+    Object.keys(defaultCodeMessages),
+    Object.keys(extractedCodeTranslations),
+  );
+  if (unusedDefaultCodeMessages.length > 0) {
+    console.warn(
+      chalk.yellow(`Unused default message codes found.
+Please report this Docusaurus issue.
+- ${unusedDefaultCodeMessages.join('\n- ')}
+`),
+    );
+  }
+
+  return mapValues(
+    extractedCodeTranslations,
+    (messageTranslation, messageId) => {
+      return {
+        ...messageTranslation,
+        message: defaultCodeMessages[messageId] ?? messageTranslation.message,
+      };
+    },
+  );
+}