Question

I’m currently working on a site that detects the browser version by checking for various JS objects:

var is = { 
  ff: window.globalStorage, 
  ie: document.all && !window.opera, 
  ie6: !window.XMLHttpRequest, 
  ie7: document.all && window.XMLHttpRequest && !XDomainRequest && !window.opera, 
  ie8: document.documentMode==8, 
  opera: Boolean(window.opera), 
  chrome: Boolean(window.chrome), 
  safari: window.getComputedStyle && !window.globalStorage && !window.opera 
} 

However this doesn’t work in FireFox 4. Does anyone know what objects to check for, when you want to detect FF4?

Answer 1

Just check for something that was introduced with Gecko 2.0, such as selection.modify:

window.globalStorage && window.getSelection().modify

and window.globalStorage won’t return all versions of FF, as it requires Gecko 1.8.1 / FF2