Re-enable javascript dialog

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Works every time.

Let me present an alternative answer from what you're asking, as I think alerts() are a rather time consuming way to debug, especially when you're using Chrome as your development platform.

Developing with the aid of various console functions you can get a more streamlined debugging workflow set into place.

I understand that alerts() are sometimes good to stop the execution to read your code - although console has commands to cater for this as well:

debugger;

for( var x = 0; x < 10; x++ ) {
   if ( x == 5 ) 
       debugger;  //Console opens, press F8 to resume or F10 to step into.
}

Console.warn and Console.log

   for( var y = 10; y > 0; y-- ) {
      if ( y == 4 ) 
         console.warn( 'Oh no!', y );
      else
         console.log( 'Normal:', y );
   }