How to know if the client's browser has firebug enabled? [duplicate]

This question already has answers here: Closed 11 years ago.

Possible Duplicate:

How can the page know I开发者_StackOverflow'm analyzing it with firebug

This is question just out of curiousity, When i was browsing gmail with firebug enabled gmail shows up a message that firebug has known to make gmail slow if not prperly configured. So was just wondering how they do it.. Any ideas?

---

I think this should work:

  if (window.console && window.console.firebug) { 
         // do something if firebug 
         alert("Firebug running"); 
     }