jquery - Cross-browser image onload event handling

Question

In the jQuery docs for the load event http://api.jquery.com/load-event/, it says Can cease to fire for images that already live in the browser's cache. Is any more information available on this, such as what browsers it affects, and in what situations?

Answer 1

I'm not sure what browsers are affected, but it is easy to check for.

var img = new Image();
img.src = "foo.jpg";
if (img.complete || img.readyState === 4) {
    // image is cached
    doneCallback();
}
else {
    $(img).on('load',doneCallback);
}

UPDATE

If you change the code around, it will consistently fire a load event in all browsers.

var img = new Image();
$(img).load(doneCallback);
img.src = "foo.jpg";