JavaScript method to determine whether firebug is enabled

This article describes the method of javascript to determine whether firebug is enabled. Share it for your reference, as follows:

Friends who often use Firefox + Firebug to debug JavaScript know that once firebug is turned on, the running of the page js will significantly slow down.

Can the page's javascript actively determine whether the current Firebug is enabled?

The answer is yes.

Firebug has been updated in many versions. I remember that an old version can be judged by detection, but it is now invalid.

The recent versions of firebug can be judged by the() method, and its return value is a string "_firebugIgnore"

The complete demo code is as follows:

<input type="button" value="check_firebug" onclick="check_firebug()">
<script>
function check_firebug(){
  if(  && ( ||  && /firebug/(()) ) ){
    alert('Firebug is running');
  }else{
    alert('No Firebug detected');
  }
}
</script>

This method also has a disadvantage. After closing firebug, () still returns "_firebugIgnore", and the page needs to be refreshed. But for most cases, it's enough.

The () method was originally used to view variables or objects in the form of a table, and the parameters were passed as the variables or objects to be viewed. If you don’t pass the argument, you will return this "_firebugIgnore". Is it considered an easter egg?

For example (run in the firebug console):

arr=[["aaaa",1,2,3],["bbbb",4,5,6]];
(arr);

More advanced usages of () canView here。

For more information about JavaScript, readers who are interested in reading this site's special topic:Summary of JavaScript window operations and techniques》、《JavaScript traversal algorithm and skills summary》、《Summary of JavaScript switching effects and techniques》、《Summary of JavaScript search algorithm skills》、《Summary of JavaScript animation special effects and techniques》、《Summary of JavaScript Errors and Debugging Skills》、《Summary of JavaScript data structure and algorithm techniques"and"Summary of JavaScript mathematical operations usage》

I hope this article will be helpful to everyone's JavaScript programming.