diff --git a/background/background.js b/background/background.js
index d4b516f7..2dfe2054 100644
--- a/background/background.js
+++ b/background/background.js
@@ -317,11 +317,13 @@ function updateIcon(tab, styles) {
       }
       // Vivaldi bug workaround: setBadgeText must follow setBadgeBackgroundColor
       chrome.browserAction.setBadgeBackgroundColor({color});
-      getTab(tab.id).then(realTab => {
-        // skip pre-rendered tabs
-        if (realTab.index >= 0) {
-          chrome.browserAction.setBadgeText({text, tabId: tab.id});
-        }
+      setTimeout(() => {
+        getTab(tab.id).then(realTab => {
+          // skip pre-rendered tabs
+          if (realTab.index >= 0) {
+            chrome.browserAction.setBadgeText({text, tabId: tab.id});
+          }
+        });
       });
     });
   }
@@ -376,7 +378,7 @@ function onRuntimeMessage(request, sender, sendResponseInternal) {
 
     case 'closeTab':
       chrome.tabs.remove(request.tabId || sender.tab.id, () => {
-        if (chrome.runtime.lastError) {
+        if (chrome.runtime.lastError && request.tabId !== sender.tab.id) {
           sendResponse(new Error(chrome.runtime.lastError.message));
         }
       });
diff --git a/js/prefs.js b/js/prefs.js
index a0238e92..1888a435 100644
--- a/js/prefs.js
+++ b/js/prefs.js
@@ -299,7 +299,7 @@ var prefs = new function Prefs() {
 
   // Polyfill for Firefox < 53 https://bugzilla.mozilla.org/show_bug.cgi?id=1220494
   function getSync() {
-    if ('sync' in chrome.storage) {
+    if ('sync' in chrome.storage && !chrome.runtime.id.includes('@temporary')) {
       return chrome.storage.sync;
     }
     const crappyStorage = {};
@@ -313,7 +313,9 @@ var prefs = new function Prefs() {
             crappyStorage[property] = source[property];
           }
         }
-        callback();
+        if (typeof callback === 'function') {
+          callback();
+        }
       }
     };
   }