Firebug is known to make Gmail slow unless.
26 November 2007

Determine if Firebug running...

So I finally got the new gmail for a few weeks now and I love it. Preloading makes life a little faster … but it warns me about firebug … How did it know?

After some digging it was really quite simple …

if(window.console && window.console.firebug)
 alert("you are using firebug");

Try it out for yourself by clicking the following link: Is Firebug running?

Some people have a problem with this but it’s a proactive way for them to make their email be more responsive… I can’t live without Firebug, because it’s a great tool, BUT I keep Firebug disabled most of the time because it slows my browsing experience.

Cool !


I’ve my Firebug on… but the script say that is not…


Your code won’t work if there is an extension which has “Console object” ..
Actually, the console object is just a Javascript object. Other Firefox extensions can create the console object in their code..


but ya. if you are using this code then it might work as long as other developer doesn’t create other extension based on Firebug..

Michael Sync

darcas: what version of firebug do you have. Is it enabled… I have mine enabled from “add-on” section but disabled from the firebug menu and it rightly tells me not running.

Daniel Bulli2

michael: thanks for commenting. it’s true i can’t stop another developer from using firebug as a base OR falsely represent themselves …

Daniel Bulli2

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