Issue 6436 - Thread access crash

libadblockplus-android-webview/src/org/adblockplus/libadblockplus/android/webview/AdblockWebView.java

 /*
  * 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 1136 matching lines @@
 
     loading = true;
     addDomListener = true;
     elementsHidden = false;
     loadError = null;
     url = newUrl;
 
     if (url != null)
     {
       elemHideLatch = new CountDownLatch(1);
-      elemHideThread = new ElemHideThread(elemHideLatch);
-      elemHideThread.setFinishedRunnable(elemHideThreadFinishedRunnable);
-      elemHideThread.start();
+      synchronized (elemHideThreadLockObject)
+      {
+        elemHideThread = new ElemHideThread(elemHideLatch);
+        elemHideThread.setFinishedRunnable(elemHideThreadFinishedRunnable);
+        elemHideThread.start();
+      }
     }
     else
     {
       elemHideLatch = null;
     }
   }
 
   private void buildInjectJs()
   {
     try
@@ skipping 283 matching lines @@
         w("Busy with elemhide selectors, delayed disposing scheduled");
         elemHideThread.setFinishedRunnable(disposeRunnable);
       }
       else
       {
         disposeRunnable.run();
       }
     }
   }
 }