Keep window positions relative to display
When the display layout is changed, windows will retain their absolute coordinates, even if a display changes coordinates (except for tiled windows, #513).
Example: I have a sole laptop with a window
foo on it. After arriving at the office, I plug it into an external display to the left of the laptop, and activate the corresponding display profile to enable both displays.
foo now resides on the external monitor.
It would make sense for the window manager to move windows in this case. Window positions should be kept relative to their display, instead of using absolute coordinates.