diff --git a/services/sync/modules/SyncDisconnect.jsm b/services/sync/modules/SyncDisconnect.jsm
index 9ac237f771fa..02da5be0557b 100644
--- a/services/sync/modules/SyncDisconnect.jsm
+++ b/services/sync/modules/SyncDisconnect.jsm
@@ -23,9 +23,9 @@ XPCOMUtils.defineLazyGetter(this, "FxAccountsCommon", function() {
   return ChromeUtils.import("resource://gre/modules/FxAccountsCommon.js");
 });
 
-this.EXPORTED_SYMBOLS = ["SyncDisconnectInternal", "SyncDisconnect"];
+const EXPORTED_SYMBOLS = ["SyncDisconnectInternal", "SyncDisconnect"];
 
-this.SyncDisconnectInternal = {
+const SyncDisconnectInternal = {
   lockRetryInterval: 1000, // wait 1 seconds before trying for the lock again.
   lockRetryCount: 120, // Try 120 times (==2 mins) before giving up in disgust.
   promiseDisconnectFinished: null, // If we are sanitizing, a promise for completion.
@@ -226,7 +226,7 @@ this.SyncDisconnectInternal = {
   },
 };
 
-this.SyncDisconnect = {
+const SyncDisconnect = {
   get promiseDisconnectFinished() {
     return SyncDisconnectInternal.promiseDisconnectFinished;
   },
diff --git a/services/sync/modules/engines/prefs.js b/services/sync/modules/engines/prefs.js
index 24b488d15a4b..46be11f92019 100644
--- a/services/sync/modules/engines/prefs.js
+++ b/services/sync/modules/engines/prefs.js
@@ -62,7 +62,7 @@ XPCOMUtils.defineLazyGetter(this, "PREFS_DOC_URL", () =>
 );
 
 // Check for a local control pref or PREF_SYNC_PREFS_ARBITRARY
-this.isAllowedPrefName = function(prefName) {
+function isAllowedPrefName(prefName) {
   if (prefName == PREF_SYNC_PREFS_ARBITRARY) {
     return false; // never allow this.
   }
@@ -80,7 +80,7 @@ this.isAllowedPrefName = function(prefName) {
   } catch (_) {
     return false;
   }
-};
+}
 
 function PrefRec(collection, id) {
   CryptoWrapper.call(this, collection, id);