Issue 6437 - Skip DOM-only patterns on initial load

lib/content/elemHideEmulation.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 438 matching lines @@
     return getCachedPropertyValue(
       this, "_dependsOnCharacterData",
       () => this.selectors.some(selector => selector.dependsOnCharacterData)
     );
   }
 };
 
 function filterPatterns(patterns, {stylesheets, mutations})
 {
   if (!stylesheets && !mutations)
-    return patterns.slice();
+    return patterns.filter(pattern => pattern.dependsOnStyles);
 
   return patterns.filter(
     pattern => (stylesheets && pattern.dependsOnStyles) ||
                (mutations && pattern.dependsOnDOM)
   );
 }
 
 function shouldObserveAttributes(patterns)
 {
   return patterns.some(pattern => pattern.maybeDependsOnAttributes);
@@ skipping 338 matching lines @@
           characterData: shouldObserveCharacterData(this.patterns),
           subtree: true
         }
       );
       this.document.addEventListener("load", this.onLoad.bind(this), true);
     }
   }
 };
 
 exports.ElemHideEmulation = ElemHideEmulation;