tor-browser

commit 5b860ce34a5cc47618f1433d6671c90745f0a4a6
parent ea90b161fe6c4fc6ce870312f1a1c6190b07bb94
Author: Harsheet <hsohaney@mozilla.com>
Date:   Wed, 22 Oct 2025 12:22:29 +0000

Bug 1994874 - Don't backup the user's backup preferences. r=cdupuis,sthompson

Differential Revision: https://phabricator.services.mozilla.com/D269288

Diffstat:
M
browser/components/backup/resources/PreferencesBackupResource.sys.mjs
 | 
5
++++-
M
browser/components/backup/tests/xpcshell/test_PreferencesBackupResource_Nimbus.js
 | 
15
+++++++++++++++

2 files changed, 19 insertions(+), 1 deletion(-)
diff --git a/browser/components/backup/resources/PreferencesBackupResource.sys.mjs b/browser/components/backup/resources/PreferencesBackupResource.sys.mjs
@@ -36,12 +36,15 @@ export class PreferencesBackupResource extends BackupResource {
    */
   static addPrefsToIgnoreInBackup(prefsOverrideMap) {
     // List of prefs we never backup.
-    const kIgnoredPrefs = [
+    let kIgnoredPrefs = [
       "app.normandy.user_id",
       "toolkit.telemetry.cachedProfileGroupID",
       PROFILE_RESTORATION_DATE_PREF,
     ];
 
+    const backupPrefs = Services.prefs.getChildList("browser.backup.");
+    kIgnoredPrefs = kIgnoredPrefs.concat(backupPrefs);
+
     // Prefs with this prefix are always overriden.
     const kNimbusMetadataPrefPrefix = "nimbus.";
 
diff --git a/browser/components/backup/tests/xpcshell/test_PreferencesBackupResource_Nimbus.js b/browser/components/backup/tests/xpcshell/test_PreferencesBackupResource_Nimbus.js
@@ -188,6 +188,20 @@ function checkNimbusHasSetPrefs() {
   Assert.deepEqual(jsonTestValue, parsedJson);
 }
 
+async function checkIgnoredBackupPrefs(backupPrefsFilePath) {
+  let contents = (await IOUtils.readUTF8(backupPrefsFilePath))
+    .split("\n")
+    .map(line => line.trim());
+
+  let checkPrefNotSerialized = pref => {
+    Assert.ok(
+      !contents.reduce((acc, line) => acc || line.includes(pref), false)
+    );
+  };
+
+  checkPrefNotSerialized("browser.backup.");
+}
+
 async function checkBackupIgnoredNimbusPrefs(backupPrefsFilePath) {
   let contents = (await IOUtils.readUTF8(backupPrefsFilePath))
     .split("\n")
@@ -281,6 +295,7 @@ add_task(async function test_prefs_backup_does_not_backup_nimbus_prefs() {
   checkNimbusHasSetPrefs();
   const { sandbox, stagingPath, sourcePath } = await performBackup();
   await checkBackupIgnoredNimbusPrefs(PathUtils.join(stagingPath, "prefs.js"));
+  await checkIgnoredBackupPrefs(PathUtils.join(stagingPath, "prefs.js"));
   await maybeRemovePath(stagingPath);
   await maybeRemovePath(sourcePath);
   sandbox.restore();