GNOME Bugzilla – Bug 776548
Placing HiDPI screens is confusing
Last modified: 2017-09-15 13:45:27 UTC
When using 2 screen and having one of them being HiDPI, it's pretty confusing to place screens around. Let's say you have a 13" laptop screen at 3200x1800 and a 26" external monitor at 2560x1440, the display panel of the control center will show the laptop screen with a bigger thumbnail. As a result you tend to think the bigger thumbnail is your external screen (because that's what you see from the outside). It took a while to figure that the control center wasn't misplacing the screen and that everything is actually in working order. It would probably be a good idea to normalize the thumbnail's size using the scaling factor.
This is working correctly in 3.26. To see it in action you need to enable the fractional scaling support though (i.e. use a wayland session and set the dconf /org/gnome/mutter/experimental-features list to include 'scale-monitor-framebuffer'). *** This bug has been marked as a duplicate of bug 782785 ***