It seems like this has been asked a million times, but nothing seems to answer my question.
I include it in my .xul above my other scripts- (I checked the location and it's correct). It's the first time I've used jQuery in an extension, so I'm trying to run some commands on load just to see if it works. The following below throws no exceptions: window.addEventListener("load", function() { init(); }, false) var init = function() { try { jQuery.noConflict(); } catch(e) { alert(e); } } Below I'll list a bunch of things I tried with their respective errors to maybe help give a glimpse into whats going on... What's going on here? I'm sure it's something obvious, or simple... The following: window.addEventListener("load", function() { init(); }, false) var init = function() { try { jQuery.noConflict(); alert(jQuery("body")); } catch(e) { alert(e); } } Throws: TypeError: n.find is not a function The Following: window.addEventListener("load", function() { init(); }, false) var init = function() { try { $.getJSON("http://www.google.com/", function(data) { alert(data); }); } catch(e) { alert(e); } } Throws: TypeError: $.getJSON is not a function The Following: window.addEventListener("load", function() { init(); }, false) var init = function() { try { jQuery.noConflict(); jQuery.getJSON("http://www.google.com/", function(data) { alert(data); }); } catch(e) { alert(e); } } Throws: TypeError: jQuery.getJSON is not a function Thanks, guys!