Window is off-screen after unplugging a secondary display

[Gerry Boland]

Steps to repro
1. mir_proving_server --display-config=sidebyside
2. mir_demo_client_egltriangle
3. plug in a secondary display
4. move triangle to secondary display
5. unplug secondary display

Expected result
triangle moved to primary display

Actual result
triangle in no-man's land

[Daniel van Vugt (vanvugt)]

Last time I tested this, it seemed to work. However I was probably testing windows residing on the left screen and not the right. So they did not need to move in order to still be on screen when the second monitor was removed.

[Daniel van Vugt (vanvugt)]

Confirmed: if the client is on the removed display and that display is _not_ the top left one, then you will lose sight of the client window. If however you removed the top-left display then the remaining displays reshuffle and your app will still be on screen.

Workaround for mir_proving_server: Alt+Tab to the window then Alt+mousedrag to pull the window over from off-screen.
Workaround for Unity7/Compiz: Alt+Tab to the window then Alt+F7 to grab it and pull the window over from off-screen.

No known workarounds for mir_demo_server*. However I expect they will be the first to get fixes because this is directly related to window management (DisplayLayout changes and window placement).