Issue 5353 - Add advanced element hiding filters documentation

pages/filter-cheatsheet.html

Index: pages/filter-cheatsheet.html
===================================================================
--- a/pages/filter-cheatsheet.html
+++ b/pages/filter-cheatsheet.html
@@ -165,16 +165,20 @@
   {
     vertical-align: top;
     padding: 5px;
   }
   td > p:first-child
   {
     margin-top: 0px;
   }
+  td > code
+  {
+    overflow-wrap: break-word;
+  }
   .syntax
   {
     width: 10%;
   }
   .purpose
   {
     width: 45%;
   }
@@ -787,8 +791,59 @@
     <td>{{s137 Matches div elements that end the style specified}}</td>
   </tr>
   <tr>
     <td><code>##div[style*=&quot;width:300px;height:250px;&quot;]</code></td>
     <td>{{s138 Matches div elements that containing the style specified}}</td>
   </tr>
 </table>
 <p>{{s139 The above filters are only examples of valid element hiding rules. Any <a href="http://www.w3.org/TR/css3-selectors/">CSS selector</a> supported by Firefox can be used for element hiding.}}</p>
+
+<h2 id="elementhideemulation">{{s140 Advanced element hiding}}</h2>
+
+<p>{{s141 <code><fix>#?#</fix></code> indicate an advanced element hiding rule. Unlike the element hiding rules, these require to be specific and therefor to have <a href="#elementdomains">domain selection</a> not be empty. When used with a valid CSS selector, it will hide the elements directly. All the examples of <a href="#elementselection">element selection</a> above apply (replace <code><fix>##</fix></code> with <code><fix>#?#</fix></code>). These filters also support advanced element selection that are Adblock Plus extensions to CSS.}}</p>
+
+<p>{{s142 This is a new feature in Adblock Plus 1.13.3 for Chrome and Opera}}.</p>
+
+<h3>{{s143 Advanced element selection}}</h3>
+
+<p>{{s148 Here are the pseudo-classes implemented for the advanced element selection}}</p>
+
+<table>
+  <col class="selector">
+  <col class="selectorPurpose">
+  <tr>
+    <th>{{s149 Pseudo-class}}</th>
+    <th>{{s127 Purpose}}</th>
+  </tr>
+  <tr>
+    <td><code>:-abp-properties()</code></td>
+    <td>{{s150 Select an element if its CSS style properties match the one specified}}</td>
+  </tr>
+  <tr>
+    <td><code>:-abp-has()</code></td>
+    <td>{{s151 Select an element if its content subtree match the selector specified}}</td>
+  </tr>
+</table>
+
+<p>{{s144 These few examples show how to use the pseudo-class form of the advanced element selection}}</p>
+
+<table>
+  <col class="selector">
+  <col class="selectorPurpose">
+  <tr>
+    <th>{{s126 Selector}}</th>
+    <th>{{s127 Purpose}}</th>
+  </tr>
+  <tr>
+    <td><code>#?#div:-abp-properties(width:300px;height:250px;)</code></td>
+    <td>{{s145 Matches <code><fix>div</fix></code> elements whose style contain the specified properties}}</td>
+  </tr>
+  <tr>
+    <td><code>#?#div:-abp-has(> div > img.advert)</code></td>
+    <td>{{s146 Matches <code><fix>div</fix></code> elements that contain as a direct descendant a <code><fix>div</fix></code> containing an <code><fix>img</fix></code> with the class "advert"}}</td>
+  </tr>
+  <tr>
+    <td><code>#?#div:-abp-has(> div > img:-abp-properties(width:300px;height:250px;))</code></td>
+    <td>{{s147 Matches <code><fix>div</fix></code> elements that contain as a direct descendant element matching the selector: a <code><fix>div</fix></code> that has a child <code><fix>img</fix></code> whose style properties contain the specified properties}}</td>
+  </tr>
+</table>
+