I found this problem after migration from Gentoo to Debian. Debian 8 uses xfce4-session compiled with --disable-legacy-sm by default, so I got some uggly QT applications because of it. Examples: skype, qtconfig. Here are screenshots for qtconfig which is easy to reproduce: 1) http://prntscr.com/7kmav7 // xfce4-session with --enable-legacy-sm (default) 2) http://prntscr.com/7kmb1k // --disable-legacy-sm (default for debian 8) The first one looks great, the second one looks and behaves uggly for me. There's probably something in xfsm-legacy code responsible for qt4/gtk+ themeing integration which is disabled when --disable-legacy-sm switch is used. Thanks for attention.
Does your own build of xfce4-session work? I have tried to build xfce4-session from git but after installing it I see only black screen after logging in.
*** Bug 11643 has been marked as a duplicate of this bug. ***
(In reply to yanpaso from comment #1) > Does your own build of xfce4-session work? I have tried to build > xfce4-session from git but after installing it I see only black screen after > logging in. Hello, Yanpaso. To resolve the issue I just made my own version of Debian's package for xfce4-session with --enable-legacy-sm flag. I didn't try xfce4-session from git. The package version I used is pointed correctly in the bug report: 4.10.1
Oh, I see. I wasn't able to build 4.12 manually, but Mint devs has already published build of xfce4-session v4.12 without flag --disable-legacy-sm, so I'm happy now :)