Created attachment 103858 [details] Screenshot of the Settings menu in Clementine GUI of all applications using qt4 libraries (clementine, k3b, etc) has a very-bad looking as it seems to fallback to some very basic theming (no breeze theme, see attached screenshot with Clementine). The problem arises just after last week Neon LTS upgrade from qt 5.7.0 to 5.7.1. I checked all qt4 libraries clementine relies on ('ldd clementine'), and they are all correctly referenced in /usr/lib/x86_64-linux-gnu/. I checked the apt log, and none of them were recently upgraded (which might have explained the regression). I also flushed my clementine user data and re-installed clementine from scratch using the clementine official repo, and I even compiled the source code of Clementine directly on my platform (no compilation warnings and everything went smooth) but the issue still persists.
Comment on attachment 103858 [details] Screenshot of the Settings menu in Clementine works for me, do you have kde-style-breeze-qt4 installed?
(In reply to Jonathan Riddell from comment #1) Hi Jonathan, kde-style-breeze-qt4 is installed: $ sudo dpkg -l | grep kde-style- ii kde-style-breeze 4:5.8.5-0neon+16.04+build3 amd64 Widget style for Qt and KDE Software ii kde-style-breeze-qt4 4:5.8.5-0neon+16.04+build3 amd64 Widget style for Qt 4 and KDE Software ii kde-style-qtcurve-qt4:amd64 1.8.18+git20160112-0cd6aae-1 amd64 QtCurve widget style for applications based on Qt 4.x $ sudo apt-cache policy kde-style-breeze-qt4 kde-style-breeze-qt4: Installed: 4:5.8.5-0neon+16.04+build3 Candidate: 4:5.8.5-0neon+16.04+build3 Version table: *** 4:5.8.5-0neon+16.04+build3 500 500 http://archive.neon.kde.org/user/lts xenial/main amd64 Packages 100 /var/lib/dpkg/status 4:5.8.5-0neon+16.04+build2 500 500 http://archive.neon.kde.org/user/lts xenial/main amd64 Packages 4:5.8.4-0neon+16.04+build1 500 500 http://archive.neon.kde.org/user/lts xenial/main amd64 Packages 4:5.5.5-0ubuntu1 500 500 http://be.archive.ubuntu.com/ubuntu xenial/universe amd64 Packages It used to work fine (Clementine, k3b and alike qt4 applications all beautifully themed), but since the last KDE Neon upgrade last week, I got this regression.
I first fixed the issue by configuring another theme with qtconfig-qt4 (GTK+ instead of default desktop settings). Then I realized that, by removing ~/.config/Trolltech.conf wherein all qt4 settings seem to be stored, Clementine falls back on the correct qt4 Breeze theme. Nothing to do with KDE Neon upgrade (or maybe some updated package did modify my Trolltech.conf file). The bug can be closed. Thanks Jonathan for having a look.
Created attachment 104120 [details] Clementine after deletion of Trolltech.conf file