Ubuntu – Graphical components stuck on Kubuntu 16.04


I have Kubuntu 16.04 with kde 5.6.5, and I cannot change the graphical components, I am stuck with the qtcurve style.

Here is a screenshot of the settings, as you can see, the style selected (and applied) is Fusion, but the qtcurve is still used.
enter image description here

I am using a laptop with intel graphics and nvidia card, and I had problems insalling drivers because of the optimus system.
While trying to reinstall my graphics drivers, I ended up installing the ubuntu desktop on my system (I don't remember the exact command).
On the login screen, I can now choose between plasma and Ubuntu.

I don't know if it's related, but I thought it was useful to mention it.

I tried rebooting, no luck.

This is not an urgent problem (qtcurve style is good), but this is annoying and I like having a working system 😀

Any help is welcome.

Best Answer

  • Cause of the Problem

    I experienced this same problem yesterday and discovered that, some packages was overriding QT style with gtk looks. The environment variables in question were QT_STYLE_OVERRIDE and QT_QPA_PLATFORMTHEME.


    The solution is putting these lines in ~/.profile file to unset the environment variables.

    ## Fixing QT style override problem
    if [ "x$XDG_SESSION_DESKTOP" == "xKDE" ] || [ "x$XDG_SESSION_DESKTOP" == "xplasma" ];
        unset QT_STYLE_OVERRIDE

    Now, the style should be changeable and will persist.

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