Thanks for contributing! Can you please provide a test case using a test like jsfiddle.net or jsbin.com or some other hosted solution so we can see the issue in action to determine if this is a bug? Thanks!

To be more exact, I see that in Firefox 15.0 and his firebug.

I don't succeed to do ajax calling with jsfiddle or other. But, I've found where the problem comes from!

It's in the globalEval function of core.js (from 1.6 version) :

// Evaluates a script in a global context
// Workarounds based on findings by Jim Driscoll
// http://weblogs.java.net/blog/driscoll/archive/2009/09/08/eval-javascript-global-context
globalEval: function( data ) {
	if ( data && rnotwhite.test( data ) ) {
		// We use execScript on Internet Explorer
		// We use an anonymous function so that context is window
		// rather than jQuery in Firefox
		( window.execScript || function( data ) {
			window[ "eval" ].call( window, data );
		} )( data );
	}
},

Firefox doesn't like ''window[ "eval" ].call( window, data );'' and put the content of ''data'' twice in the page.

If I use ''window.eval(data);'', it's ok.

I can not reproduce this: http://jsfiddle.net/5NcPp/1/ Please let me know what to change to show the bug happening.

I see the bug on your page when I look with Firebug. It doesn't open the confirm twice (normal) but the hello implementation is in double.

Screenshot : http://img824.imageshack.us/img824/456/image1ksm.jpg

I still can not reproduce... http://jsfiddle.net/5NcPp/2/ if it truly was in the source twice though, this new fiddle should print hi2. Does it? If not, I'm inclined to call this a bug in firebug and not jquery. Please let me know.

Nop, it print hi1.

Screenshot : http://img163.imageshack.us/img163/2208/image2gg.jpg

You suppose that if there are 2 hello functions, it will go in each of them. But, maybe it just goes in the first hello function found and never in the other. So, it will never print hi2. I've also tried with a append() on the title and it is executed just one time.

Me, I suppose that Firefox (not Firebug) have a bug with ''window[ "eval" ].call( window, data );'' in the version 15.0 (before, I don't know). If it's true, JQuery will need find something for this exception like it has ever done for IE and old chrome version (read http://weblogs.java.net/blog/driscoll/archive/2009/09/08/eval-javascript-global-context).

Sorry, but that not how JavaScript scoping works. If it was truly in there twice, it would have printed hi2. The only conclusion I can come to is that this isn't a bug in jQuery nor Firefox. Until we can prove this has some ill effect other than appearing incorrectly in the firebug console, I must close this as not a bug. Please feel free to reply if you can prove otherwise, and I'll gladly reopen! Thanks again for contributing!

So, why in this test : http://jsfiddle.net/vax82/ ... I just see "2!" and not "1...2!" ? He just call one hello function, not two.

my point wasn't that the function would be called twice... My point was that "a" would've been incremented twice. Firefox's eval shows the hoisted source code, that's all that's happening.