diff --git a/platform/common/vapi-background.js b/platform/common/vapi-background.js
index 52907b8e0..fd1820232 100644
--- a/platform/common/vapi-background.js
+++ b/platform/common/vapi-background.js
@@ -668,7 +668,7 @@ if ( webext.browserAction instanceof Object ) {
 // https://github.com/uBlockOrigin/uBlock-issues/issues/32
 //   Ensure ImageData for toolbar icon is valid before use.
 
-vAPI.setIcon = (( ) => {
+{
     const browserAction = vAPI.browserAction;
     const  titleTemplate =
         browser.runtime.getManifest().browser_action.default_title +
@@ -765,7 +765,7 @@ vAPI.setIcon = (( ) => {
     //        bit 2 = badge color
     //        bit 3 = hide badge
 
-    return async function(tabId, details) {
+    vAPI.setIcon = async function(tabId, details) {
         tabId = toTabId(tabId);
         if ( tabId === 0 ) { return; }
 
@@ -808,7 +808,7 @@ vAPI.setIcon = (( ) => {
             vAPI.contextMenu.onMustUpdate(tabId);
         }
     };
-})();
+}
 
 browser.browserAction.onClicked.addListener(function(tab) {
     vAPI.tabs.open({
diff --git a/src/js/tab.js b/src/js/tab.js
index 1bd03c180..2e38931a1 100644
--- a/src/js/tab.js
+++ b/src/js/tab.js
@@ -1059,7 +1059,7 @@ vAPI.tabs = new vAPI.Tabs();
 
 // Update visual of extension icon.
 
-µb.updateToolbarIcon = (( ) => {
+{
     const tabIdToDetails = new Map();
 
     const computeBadgeColor = (bits) => {
@@ -1118,7 +1118,7 @@ vAPI.tabs = new vAPI.Tabs();
     //        bit 2 = badge color
     //        bit 3 = hide badge
 
-    return function(tabId, newParts = 0b0111) {
+    µb.updateToolbarIcon = function(tabId, newParts = 0b0111) {
         if ( typeof tabId !== 'number' ) { return; }
         if ( vAPI.isBehindTheSceneTabId(tabId) ) { return; }
         const currentParts = tabIdToDetails.get(tabId);
@@ -1133,7 +1133,7 @@ vAPI.tabs = new vAPI.Tabs();
         }
         tabIdToDetails.set(tabId, newParts);
     };
-})();
+}
 
 /******************************************************************************/