Issue 6652 - Do not push to unconditional selectors array

lib/elemHide.js

Index: lib/elemHide.js
===================================================================
--- a/lib/elemHide.js
+++ b/lib/elemHide.js
@@ -89,17 +89,17 @@
  * 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 = {
   /**
@@ -255,19 +255,16 @@
    *                         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)
     {
@@ -293,11 +290,14 @@
 
       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;
   }
 };