PreventDefault in 'mousedown' cancels 'mousemove', 'mouseup' and 'mouseout' events outside of iframe.
Witout preventDefault all works fine.
I just ran into this issue today, where this works fine in Firefox, but fails in Safari and Chrome. Since the original URL no longer seems to work, I've attached a testcase where commenting out the call to `event.preventDefault()` in the `mousedown` event handler shows that mouse events are dispatched even when outside the iframe bounds.
Created attachment 249033 [details]
Created attachment 249034 [details]
Additional testcase content
Raised a Chromium bug too at https://code.google.com/p/chromium/issues/detail?id=468730.
Mass move bugs into the DOM component.