Workaround (2) Blindly slide back to the workspace where the window came from and force a new window to open above the fullscreen window. e.g. Ctrl+Alt+T. Now the fullscreen window is no longer on top an is redirected again. So you can slide.
Workaround (2)
Blindly slide back to the workspace where the window came from and force a new window to open above the fullscreen window. e.g. Ctrl+Alt+T. Now the fullscreen window is no longer on top an is redirected again. So you can slide.