ceae032112
Windows can be restacked at any time, including when the stackAbove property of the window clone is being dragged, and thus parented to the uiGroup. To do stacking properly, we need to skip it for the duration of the drag, and sync it again at the end (which is already done by mutter because of the workspace change) https://bugzilla.gnome.org/show_bug.cgi?id=685285