I forgot to specify that I tried with different versions of the core... 1.7.2, 1.6.1, 1.4.3 and the bug is the same.

This is not a jQuery bug. http://jsfiddle.net/rwaldron/PxBwk/

As I said in my ticket, it depends on WHERE the jQuery core is included. I'm not sure how jQuery is loaded in jsFiddle so I used your jsFiddle code to create a few examples: (Don't forget that this bug happens only in Firefox.)

Not working example (with jQuery in the body):

http://test.lesaffranchis.ca/video/jquery_test.html

Working example (with jQuery in the head):

http://test.lesaffranchis.ca/video/jquery_test2.html

On the first try, usually all events will be fired in the "body" example. But if you reload that page a few times, you'll see that the events are not all called. (Even if you empty the browser cache).

The jQuery core is breaking the event capture even if I don't use it. In the following examples, I used addEventListener() instead of jQuery's on():

Not working example (with jQuery in the body):

http://test.lesaffranchis.ca/video/jquery_addeventlistener_body.html

Working example (with jQuery in the head):

http://test.lesaffranchis.ca/video/jquery_addeventlistener_head.html

Please, try it in a real environment. As great as jsFiddle is for quick tests, it's not the same as a standalone page.

I'm not sure how jQuery is loaded in jsFiddle

View source.

Please, try it in a real environment. As great as jsFiddle is for quick tests, it's not the same as a standalone page.

Oh, like this?

http://jsfiddle.net/rwaldron/PxBwk/show/light/

^^^ That's pretty damn real.

As you can see here...

[[Image(http://gyazo.com/ad6c02c3f77e40a5881e61c93bccf9c8.png)]]

Also, http://test.lesaffranchis.ca/video/jquery_test.html is 404'ing

I apologize for the bad links. It should have been:

http://test.lesaffranchis.ca/video/jquery_body.html

http://test.lesaffranchis.ca/video/jquery_head.html

Even with your standalone example on jsFiddle I still get the problem.

If you look at my original message, I said I was on Firefox on Win7. I see on your screenshot that you are on Mac OS X. I don't have a Mac to test right now, but maybe the bug is with the Windows version of FF only?

Anyway, I noticed something while testing more: I have the habit of doing Ctrl+F5 to force the reload of external files. Using the version with the jQuery core in the body, when I do Ctrl+F5 I do not get all the events but when I do a regular F5, the events are (most of the time) fired. But on the version with the jQuery core in the head, it's working every single time I do Ctrl+F5, or just F5...

This is still a weird behavior... But I'll admit that I'm no longer sure if it has anything to do with the jQuery core... I'm starting to think that it's something buggy/weird with Firefox's page reload procedure...

Hi gabriel,

I'm on a Windows 7 box and I'm unable to reproduce the problem on your jquery_body.html example using Firefox 11.0 and 12.0. Have you tried disabling all your add-ons?

I cannot reproduce the problem on Win7 and Firefox 12. However I can certainly see it happening. In the body case you are attaching to the loadstart event AFTER the video tag; perhaps the event already fired and you missed it.