diff --git a/anti-adblock-killer.user.js b/anti-adblock-killer.user.js
index 7ad9ac5c5..260ddca75 100644
--- a/anti-adblock-killer.user.js
+++ b/anti-adblock-killer.user.js
@@ -4164,7 +4164,7 @@ Aak = {
         var reWords2 = /kapat|disable|désactivez|désactiver|desactivez|desactiver|desative|desactivar|desactive|desactiva|deaktiviere|disabilitare|απενεργοποίηση|запрещать|állítsd le|publicités|рекламе|verhindert/i;
 
         // Antiblock.org v3 + v2 (Alternative Solution)
-        if (Aak.getLocal('aboBlockId') != 'undefined' &&
+        if (typeof Aak.getLocal('aboBlockId') != 'undefined' &&
           insertedNode.id == Aak.getLocal('aboBlockId')) {
           if (typeof Aak.uw[insertedNode.id] == 'object') { // V3
             Aak.uw[insertedNode.id] = null;