Issue 6652 - Do not push to unconditional selectors array

lib/elemHide.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 76 matching lines @@
 
 /**
  * Returns a list of selectors that apply on each website unconditionally.
  * @returns {string[]}
  */
 function getUnconditionalSelectors()
 {
   if (!unconditionalSelectors)
     unconditionalSelectors = [...filterBySelector.keys()];
 
-  return unconditionalSelectors.slice();
+  return unconditionalSelectors;
 }
 
 /**
  * Container for element hiding filters
  * @class
  */
 let ElemHide = exports.ElemHide = {
   /**
    * Removes all known filters
    */
@@ skipping 145 matching lines @@
    * @param {number} [criteria]
    *   One of the following: ElemHide.ALL_MATCHING, ElemHide.NO_UNCONDITIONAL or
    *                         ElemHide.SPECIFIC_ONLY.
    * @returns {string[]}
    *   List of selectors.
    */
   getSelectorsForDomain(domain, criteria = ElemHide.ALL_MATCHING)
   {
     let selectors = [];
 
-    if (criteria < ElemHide.NO_UNCONDITIONAL)
-      selectors = getUnconditionalSelectors();
-
     let specificOnly = (criteria >= ElemHide.SPECIFIC_ONLY);
     let excluded = new Set();
     let currentDomain = domain ? domain.toUpperCase() : "";
 
     // This code is a performance hot-spot, which is why we've made certain
     // micro-optimisations. Please be careful before making changes.
     while (true)
     {
       if (specificOnly && currentDomain == "")
         break;
@@ skipping 15 matching lines @@
         }
       }
 
       if (currentDomain == "")
         break;
 
       let nextDot = currentDomain.indexOf(".");
       currentDomain = nextDot == -1 ? "" : currentDomain.substr(nextDot + 1);
     }
 
+    if (criteria < ElemHide.NO_UNCONDITIONAL)
+      selectors = getUnconditionalSelectors().concat(selectors);
+
     return selectors;
   }
 };