Bug 134212 – Dragging aborts when source element moves away from mouse pointer.

• Component: DOM
• Status: NEW

[Tyler Waters]

Created attachment 233631 [details]
Test case showing the problem.

1. Open the attached file.
2. Drag the 'green' portion of the box, note that dragging works.
3. Drag the 'red' portion of the box, note that dragging does not work.

In the attached example, the 'dragstart' adds a class that makes the box 50px in height - if you start the drag in the top-50px portion (the green bit) it works as expected -- if however you start the drag in the bottom portion, the height is restricted and the 'dragend' event is fired immediately and no drag operation takes place. 

This is just on example -- moving the box by other means during the dragstart event will also raise the problem.... it seems that if the element cannot be found directly under the mouse position when the dragstart event finishes, the drag is aborted prematurely.

This works in FireFox(30) and IE(11), breaks in Chrome and Safari.

I encountered this today and created https://code.google.com/p/chromium/issues/detail?id=445641, using http://jsfiddle.net/j9q66ja6/1/ as a demo.

Agreed that any change which moves the placement of the target element causes a problem (ex: position, padding, etc.)

[Lucas Forschler]

Mass move bugs into the DOM component.