feat: add support for Firefox data collection permissions

Author: suveshmoza

packages/wxt/src/core/utils/manifest.ts

@@ -118,6 +118,17 @@ export async function generateManifest(
       ? undefined
       : versionName;
 
+  // Warn if building for Firefox without data_collection_permissions
+  if (
+    wxt.config.browser === 'firefox' &&
+    !userManifest.browser_specific_settings?.gecko?.data_collection_permissions
+  ) {
+    wxt.logger.warn(
+      'Firefox requires explicit data collection permissions. Consider adding `data_collection_permissions` to your manifest config.\n' +
+        'For more details, see: https://extensionworkshop.com/documentation/develop/firefox-builtin-data-consent/#specifying-data-types\n',
+    );
+  }
+
   addEntrypoints(manifest, entrypoints, buildOutput);
 
   if (wxt.config.command === 'serve') addDevModeCsp(manifest);

packages/wxt/src/types.ts

@@ -844,6 +844,38 @@ export type ResolvedPerBrowserOptions<T, TOmitted extends keyof T = never> = {
     : T[key];
 } & { [key in TOmitted]: T[key] };
 
+/**
+ * Firefox data collection permission types for personal data.
+ * See: https://extensionworkshop.com/documentation/develop/firefox-builtin-data-consent/#specifying-data-types
+ */
+export type FirefoxDataCollectionType =
+  | 'locationInfo'
+  | 'browsingActivity'
+  | 'websiteContent'
+  | 'websiteActivity'
+  | 'searchTerms'
+  | 'bookmarksInfo'
+  | 'healthInfo'
+  | 'contactInfo'
+  | 'socialInfo';
+
+/**
+ * Firefox data collection permissions configuration.
+ * See: https://extensionworkshop.com/documentation/develop/firefox-builtin-data-consent/#specifying-data-types
+ */
+export interface FirefoxDataCollectionPermissions {
+  /**
+   * Required data collection permissions. Users must opt in to use the extension.
+   * Can include personal data types or "none" to explicitly indicate no data collection.
+   */
+  required?: Array<FirefoxDataCollectionType | 'none'>;
+  /**
+   * Optional data collection permissions. Users can opt in after installation.
+   * Can include personal data types or "technicalAndInteraction" (which can only be optional).
+   */
+  optional?: Array<FirefoxDataCollectionType | 'technicalAndInteraction'>;
+}
+
 /**
  * Manifest customization available in the `wxt.config.ts` file. You cannot configure entrypoints
  * here, they are configured inline.
@@ -879,6 +911,11 @@ export type UserManifest = {
       strict_min_version?: string;
       strict_max_version?: string;
       update_url?: string;
+      /**
+       * Firefox data collection permissions configuration.
+       * See: https://extensionworkshop.com/documentation/develop/firefox-builtin-data-consent/#specifying-data-types
+       */
+      data_collection_permissions?: FirefoxDataCollectionPermissions;
     };
     gecko_android?: {
       strict_min_version?: string;