Issue 703 - Make sure that z-index of the "Block Element" dialog is the highest in the document

include.postload.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 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 100 matching lines @@
     clickHide_deactivate();
     currentElement = savedElement;
   }
 
   clickHide_filters = filters;
 
   clickHideFiltersDialog = document.createElement("iframe");
   clickHideFiltersDialog.src = ext.getURL("block.html");
   clickHideFiltersDialog.setAttribute("style", "position: fixed !important; visibility: hidden; display: block !important; border: 0px !important;");
   clickHideFiltersDialog.style.WebkitBoxShadow = "5px 5px 20px rgba(0,0,0,0.5)";
-  clickHideFiltersDialog.style.zIndex = 99999;
+
+  // make sure that the dialog is above everything else, by setting
+  // the z-index to the highest z-index used in the document plus 1
+  clickHideFiltersDialog.style.zIndex = Math.max.apply(null, Array.prototype.map.call(
+    document.all, function(el)
+    {
+      return parseInt(getComputedStyle(el).zIndex) || 0;
+    }
+  )) + 1;

[Wladimir Palant, 2014/06/24 10:31:39]

Please just use the maximum possible value for zIndex. As explained in
https://stackoverflow.com/a/491105/785541, the standard doesn't define a maximum
value but most browsers will likely limit it to the signed 32-bit integer range.
I confirmed that 0x7FFFFFFF is the highest zIndex value supported by Chrome, so
we can use it here - even higher values will be ignored anyway.

[Sebastian Noack, 2014/06/24 13:07:52]

Done.

 
   // Position in upper-left all the time
   clickHideFiltersDialog.style.left = "50px";
   clickHideFiltersDialog.style.top = "50px";
 
   // Make dialog partly transparent when mouse isn't over it so user has a better
   // view of what's going to be blocked
   clickHideFiltersDialog.onmouseout = function()
   {
     if (clickHideFiltersDialog)
@@ skipping 445 matching lines @@
 
           clickHide_deactivate();
         }
         break;
       default:
         sendResponse({});
         break;
     }
   });
 }