Issue 6423 - Observe only relevant mutation types

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 352 matching lines @@
 function shouldObserveAttributes(patterns)
 {
   // Observe changes to attributes if either there's a plain selector that
   // looks like an ID selector, class selector, or attribute selector in one of
   // the patterns (e.g. "a[href='https://example.com/']")
   // or there's a properties selector nested inside a has selector
   // (e.g. "div:-abp-has(:-abp-properties(color: blue))")
   return patterns.some(
     pattern => pattern.selectors.some(
       selector => selector.maybeDependsOnAttributes ||
-                  selector instanceof HasSelector &&
-                  selector.dependsOnStyles
+                  (selector instanceof HasSelector &&
+                   selector.dependsOnStyles)
     )
   );
 }
 
 function shouldObserveCharacterData(patterns)
 {
   // Observe changes to character data only if there's a contains selector in
   // one of the patterns.
   return patterns.some(
     pattern => pattern.selectors.some(
@@ skipping 304 matching lines @@
           characterData: shouldObserveCharacterData(this.patterns),
           subtree: true
         }
       );
       this.document.addEventListener("load", this.onLoad.bind(this), true);
     }
   }
 };
 
 exports.ElemHideEmulation = ElemHideEmulation;