[Bug 1305294] [NEW] QT uses incorrect theme when GNOME_DESKTOP_SESSION_ID is unset

[Launchpad Bug Tracker]

You have been subscribed to a public bug:

Bug discovered when launching VLC from the sound indicator applet: the
QT UI theme is wrong. The theme is correct when launched from Unity
launcher or terminal. Please see the attached screenshots.

I've tracked it down to a difference in environment in the VLC process:
When launched from indicator-sound, the variable
GNOME_DESKTOP_SESSION_ID is unset, and this causes VLC to become themed
incorrectly. (If the variable is given any value, then VLC looks
correct.)

To reproduce, either:
1) Launch VLC from indicator-sound (make sure it's not already running and has been started from somewhere else)
2) Or just start VLC like this from terminal:
$ GNOME_DESKTOP_SESSION_ID= vlc

Looks like a bug in qt4, which seems to depend on
GNOME_DESKTOP_SESSION_ID being set [to anything] to pick up the correct
theme. (The variable is deprecated, according to its default value in
Ubuntu 14.04.)

Try:
$ GNOME_DESKTOP_SESSION_ID= qtconfig

Observe theme not picked up from "Desktop settings" in qtconfig.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: qt4-qtconfig 4:4.8.5+git192-g085f851+dfsg-2ubuntu4
ProcVersionSignature: Ubuntu 3.13.0-23.45-generic 3.13.8
Uname: Linux 3.13.0-23-generic x86_64
ApportVersion: 2.14.1-0ubuntu1
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Apr  9 22:15:27 2014
InstallationDate: Installed on 2014-04-01 (8 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Beta amd64 (20140326)
SourcePackage: qt4-x11
UpgradeStatus: No upgrade log present (probably fresh install)

** Affects: upstart (Ubuntu)
     Importance: Medium
         Status: Confirmed


** Tags: amd64 apport-bug trusty
-- 
QT uses incorrect theme when GNOME_DESKTOP_SESSION_ID is unset
https://bugs.launchpad.net/bugs/1305294
You received this bug notification because you are a member of Ubuntu Foundations Bugs, which is subscribed to upstart in Ubuntu.