Having written javascript to perform various style changes to elements being hovered over, and struggled with the nightmare that is dragenter and dragleave events, I thought :-moz-drag-over would be a breath of fresh air. Just apply my styles to appropriate elements with the -moz-drag-over pseudo-class selector, what could be simpler?
It doesn't work. Of course, it does work, but it only applies the style to the exact selected element that would be the target of a dragenter or dragleave event. As anyone who has ever done this will tell you, that means that an element is not considered to be being dragged over when its children are being dragged over. Hence an element is not selected by :-moz-drag-over when its children would be selected by it. Even anonymous content! So drag over a toolbarbutton and your styles may show up for a moment before you drag over the icon or label and they disappear. What use is that?
