Dragging windows to other workspaces doesn't work in display clone mode

[Bazon Bloch <bazonbloch arcor de>]

Here on Arch with gnome-shell 3.10.1-1.

As soon as the second monitor is switched off or is used as a secondary display, not a clone, dragging windows to other workspaces works again.

Can someone reproduce this on other distributions?

(Or asked in another way: Should this bug be filed in Gnome or in Arch?)