Unable to modify display settings (GUI fails silently)

Question

I recently installed gnome-shell on Ubuntu 17.10 (I had been using Cinnamon previously). Most things are working fine, but I am unable to change my display settings at all.

I have two monitors -- a laptop screen plus an external display -- and by default, they are positioned in this configuration:

If I try to reposition them, I can click the apply button, but it doesn't affect the actual layout of the displays at all. (Other settings, like toggling the "mirror display" option don't do anything either.)

If I open the display settings by running the command gnome-control-center display, I can see the following error whenever I click apply:

** (switchboard:20969): CRITICAL **: DisplaysOverlay.vala:90:
GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod:
Method ApplyConfiguration is not implemented on interface org.gnome.Mutter.DisplayConfig

I tried Googling around a bit, and attempted a few solutions from this thread, to no avail. Any suggestions?

Are you on a default Wayland session? Then see what happens if you switch to an Xorg session. — pomsky, Apr 06 '18 at 19:48
@pomsky This is odd... I'm currently on Xorg, and unable to choose anything else. In the dropdown menu, if I select the "Ubuntu" option, "Ubuntu on Xorg" is automatically selected instead. — PullJosh, Apr 06 '18 at 22:49
Probably because your hardware doesn't support Wayland and so it's disabled by default. — pomsky, Apr 06 '18 at 22:59
@pomsky Interesting... It's a good thing this OS is smarter than I am, or I'd be in a lot of trouble. ;) — PullJosh, Apr 06 '18 at 23:07

score 1 · Answer 1 · answered Apr 07 '18 at 14:14

I ended up solving this issue myself. The solution, for me, was a program called arandr. arandr, as far as I can tell, is a GUI for xrandr -- the command line tool for managing monitor layouts.

I installed the program with:

sudo apt install arandr

It was easy to use and worked perfectly. I'm still not sure why the built-in tool doesn't work, but I'm happy to have the problem solved.

(Presumably, you could also solve this using xrandr if you know what you're doing. Unfortunately, I don't.)

score 0 · Answer 2 · answered Sep 06 '21 at 22:13

Hopefully the following is useful for other Ubuntu Unity 20.04 users with the same problem. The solution is to (re)install the unity control center:

sudo apt-get install unity-control-center

Although Ubuntu Unity 20.04 contains per default the unity control center, it happened that through the installation of other dependencies, the unity control center was replaced by the gnome control center, which, as side effect, gave the log lines about non existing "org.gnome.Mutter.DisplayConfig" in /var/log/syslog

Unable to modify display settings (GUI fails silently)

2 Answers2