Fixed visuals and working drag-drop again.
Fx115 made previously used toolbarbuttons act very strange wih drag-drop:
instead of dragging the actual button, the #text node would receive
dragstart event and a single letter would end up being dragged.
During troubleshooting, elements created via document.createXULElement
had this issues while being dragged (or acted oddly in other ways, e.g.
refusing to be dragged at all).
This includes a minor rewrite to use div-s instead of XUL components.
5f37ae4ab1