Replace deprecated i18next-parser with i18next-cli

i18next-parser.config.ts

@@ -1,32 +0,0 @@
-import type { UserConfig } from "i18next-parser";
-
-const config: UserConfig = {
-  keySeparator: ".",
-  namespaceSeparator: false,
-  contextSeparator: "|",
-  pluralSeparator: "_",
-  createOldCatalogs: false,
-  defaultNamespace: "app",
-  lexers: {
-    ts: [
-      {
-        lexer: "JavascriptLexer",
-        functions: ["t", "translatedError"],
-        namespaceFunctions: ["useTranslation", "withTranslation"],
-      },
-    ],
-    tsx: [
-      {
-        lexer: "JsxLexer",
-        functions: ["t", "translatedError"],
-        namespaceFunctions: ["useTranslation", "withTranslation"],
-      },
-    ],
-  },
-  locales: ["en"],
-  output: "locales/$LOCALE/$NAMESPACE.json",
-  input: ["src/**/*.{ts,tsx}"],
-  sort: true,
-};
-
-export default config;

i18next.config.ts

@@ -0,0 +1,20 @@
+import { defineConfig } from "i18next-cli";
+
+export default defineConfig({
+  locales: ["en"],
+  extract: {
+    input: ["src/**/*.{ts,tsx}"],
+    output: "locales/{{language}}/{{namespace}}.json",
+    defaultNS: "app",
+    keySeparator: ".",
+    nsSeparator: false,
+    contextSeparator: "|",
+    extractFromComments: false,
+    functions: ["t", "*.t", "translatedError", "i18nKey"],
+    transComponents: ["Trans"],
+  },
+  types: {
+    input: ["locales/{{language}}/{{namespace}}.json"],
+    output: "src/types/i18next.d.ts",
+  },
+});

knip.ts

@@ -11,7 +11,7 @@ export default {
   vite: {
     config: ["vite.config.ts", "vite-embedded.config.ts", "vite-sdk.config.ts"],
   },
-  entry: ["src/main.tsx", "i18next-parser.config.ts"],
+  entry: ["src/main.tsx", "i18next.config.ts"],
   ignoreBinaries: [
     // This is deprecated, so Knip doesn't actually recognize it as a globally
     // installed binary. TODO We should switch to Compose v2:

package.json

@@ -24,8 +24,8 @@
     "lint:eslint-fix": "eslint --max-warnings 0 src playwright --fix",
     "lint:knip": "knip",
     "lint:types": "tsc",
-    "i18n": "i18next",
+    "i18n": "npx i18next-cli extract",
-    "i18n:check": "i18next --fail-on-warnings --fail-on-update",
+    "i18n:check": "npx i18next-cli extract --ci",
     "test": "vitest",
     "test:storybook": "vitest --project=storybook",
     "test:unit": "vitest --project=unit",
@@ -109,7 +109,7 @@
     "global-jsdom": "^26.0.0",
     "i18next": "^25.0.0",
     "i18next-browser-languagedetector": "^8.0.0",
-    "i18next-parser": "^9.1.0",
+    "i18next-cli": "^1.61.0",
     "jsdom": "^26.0.0",
     "knip": "^5.86.0",
     "livekit-client": "^2.18.1",

src/utils/errors.ts

@@ -8,6 +8,8 @@ Please see LICENSE in the repository root for full details.
 import { t } from "i18next";
 import { type ConnectionError } from "livekit-client";
 
+import { i18nKey } from "./i18n";
+
 export enum ErrorCode {
   /**
    * Configuration problem due to no MatrixRTC backend/SFU is exposed via .well-known and no fallback configured.
@@ -251,9 +253,9 @@ export class PeerConnectionTimeoutError extends ElementCallError {
       ErrorCode.SFU_ERROR,
       ErrorCategory.NETWORK_CONNECTIVITY,
     );
-    // Mark translation key for i18n extraction
+    this.localisedMessageKey = i18nKey(
-    // t("error.peer_connection_timeout_description");
+      "error.peer_connection_timeout_description",
-    this.localisedMessageKey = "error.peer_connection_timeout_description";
+    );
     this.localisedMessageValues = {
       linkUrl:
         "https://docs.element.io/latest/element-server-suite-pro/configuring-components/configuring-matrix-rtc/#sfu-connectivity-troubleshooting",
@@ -268,9 +270,9 @@ export class LivekitConnectionError extends ElementCallError {
       ErrorCode.SFU_ERROR,
       ErrorCategory.NETWORK_CONNECTIVITY,
     );
-    // Mark translation key for i18n extraction
+    this.localisedMessageKey = i18nKey(
-    // t("error.livekit_connection_error_description");
+      "error.livekit_connection_error_description",
-    this.localisedMessageKey = "error.livekit_connection_error_description";
+    );
     this.localisedMessageValues = { reason: cause.reasonName };
   }
 }

src/utils/i18n.ts

@@ -0,0 +1,9 @@
+/*
+Copyright 2026 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+// Custom marker function to allow i18next extraction
+export const i18nKey = (key: string): string => key;