I'm trying to develop a custom coupon system, and all works with IE, but when I try to use the following code on firefox or safari on click it open link and display alert but doesn't copy text:
<script type="text/javascript">
function copy_to_clipboard(text)  
  {  
      if(window.clipboardData)  
      {  
        window.clipboardData.setData('text',text);  
      }  
      else  
      {  
      }  
      alert('<?php echo get_option('custom_message'); ?> Powered by: WpCode.net Couponica');  
      return false;  
  }
</script>
And on the link:
<a onclick="copy_to_clipboard('code to copy')" href="link to open" style="margin-left:40px;" target="_blank">
What's wrong? How can I change this to make it work on firefox?
 
     
     
     
    