I have a font-problem with different applications under ubuntu 15.04 (KeePassX, Google Chrome, Pidgin, etc.). In the first picture you can see that the font of the window title is ubuntu but the items below are some other font. In the second picture the whole dialog is in the wrong font. It should be like in picture three (which is firefox).
I have already tried to verify and clean font caches, reinstalled specific fonts and tried to set Ubuntu as default font in qtconfig (which doesn't seem to be saved).
When I log in as another user all applications are using the correct fonts. How can I solve this issue?