i have two monitors, one standard dpi and one hidpi. by default, standard dpi monitor has been selected as primary. changing default monitor to other, hidpi one and clicking apply does nothing. every time, after apply, the monitor defaults to hdmi instead of keeping one connected to display port which is visible after changing to some other settings category and then coming back.
*** Bug 444957 has been marked as a duplicate of this bug. ***
*** This bug has been marked as a duplicate of bug 442158 ***