GTK Theme is reset to Ambience on almost every reboot

[Tigran Aivazian]

On all my machines with a single monitor this bug is absent, i.e. it is specific to a dual monitor configuration only.

One of my desktops is connected to a Dell 24" (1200x1920 i.e. portrait mode, useful for editing source code) via VGA and AOC 28" (1920x1080) via DVI (btw, I noticed that xrandr says it is connected via HDMI --- this desktop doesn't even have an HDMI port, only DVI and VGA!). The Dell monitor is quite old, but of extremely high quality, which is why I still keep it. Now, being so old, in the last couple of months it has developed the following symptom: it would boot into 1024x768 (or 768x1024 to be pedantically exact) resolution and as soon as I login to unity session I would execute a script "fix-resolution.sh" which contains the following three commands:

xrandr --newmode "1920x1200_60.00" 193.16 1920 2048 2256 2592 1200 1201 1204 1242 -HSync +Vsync
xrandr --addmode VGA-1 "1920x1200_60.00"
xrandr --output VGA-1 --mode "1920x1200_60.00"

This would fix the resolution and I would continue working normally. However, even though I previously set the Theme (both GTK Theme and Window decoration theme in unity-tweak-tool) to "Radiance", the top panel becomes dark, i.e. as in Ambience. But the window decorations are light, i.e. as they should be in the "Radiance" theme.

Why did I mention the resolution switch issue above? Because I noticed, that when the computer boots with the Dell monitor in the correct resolution (by luck, i.e. maybe EDID info from the monitor gets through to the OS side?) then the top panel is correct, i.e. light as in Radiance.

The Ubuntu version is 16.04.3:

$ lsb_release -rd
Description: Ubuntu 16.04.3 LTS
Release: 16.04
$ unity --version
unity 7.4.0
$ uname -a
Linux brave 4.10.0-40-generic #44~16.04.1-Ubuntu SMP Thu Nov 9 15:37:44 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

Any ideas on how to fix the GTK Theme to Radiance? I tried setting it via System Settings/Appearance and via unity-tweak-tool and even via gnome-tweak-tool. None of the methods is sufficient to force the theme to remain set to Radiance.

[Tigran Aivazian (aivazian-tigran)]

Could this be related to which monitor was declared by the BIOS to be "primary"? This guess is based on the fact that it seems to be unpredictable, i.e. sometimes it boots in the correct resolution (and the top panel is correct "Radiance") and sometimes in the wrong resolution (and the top panel is reset back to "Ambiance").

There are settings in the BIOS for this but they use strange abbreviations like IGFX and I don't know what these abbreviations mean. (I'll try to use Google Internet Search engine and see, maybe that will be of help, though I doubt it --- Google is all about ads and business, and not about real knowledge).

[Tigran Aivazian (aivazian-tigran)]

UPDATE: with recent upgrades the problem mentioned in the Subject of this bug disappeared, i.e. the theme is no longer reset to Ambiance even when the second monitor is initialised in the wrong resolution.

But the problem of the resolution being dependent on the order of monitors discovered by BIOS (or by Linux?) still remains. To fix this I run the script shown in my first comment above.