Make Qt5 Applications Use Gtk+ Style on Ubuntu (GNOME, Unity, Etc) - Do you feel that Qt based applications (like VirtualBox, KDE Connect, VLC, qBittorrent, etc) on your Ubuntu are look awful?. Well, your not alone. Don't worry, today I'm gonna show you a quick tip to get Qt5 applications look better.

In this case, I'm running Ubuntu 18.04 LTS Bionic Beaver. I don't recommend to use this on Ubuntu 20.04 LTS Focal Fossa and 19.10 Eoan Ermine, because it can slow down launching that applications.

So, these are before and after screenshots :

Qt5 Applications Use Gtk+ Style on Ubuntu

To fix the issue and get Qt5 applications to use a GTK style is quite easy. As usual, open new Terminal window. You can do this by pressing Ctrl+Alt+T on your keyboard.

Suggested read :

Run the following command to install required package which contains Cleanlooks, Motif, Plastique, and Gtk+ 2 Qt5 styles :

sudo  apt install qt5-style-plugins

Once installed, now we have to set Qt5 applications to use the Gtk+ 2 style by running this command :

echo "export QT_QPA_PLATFORMTHEME=gtk2" >> ~/.profile

Now log out and log back in to see the changes.

After that, Qt5 applications like qBittorrent, VLC, or Virtualbox should use a Gtk+ style on Ubuntu with GNOME or Unity desktop.

I uploaded this quick tip as video to my YouTube channel. You can check the video above for more details.

So, that's all I can share about how to fix Qt5 applications to use a Gtk+ 2 style in Debian and Ubuntu and its derivatives system (like Elementary OS maybe?. I don't know :D). See you in the next Linux theming tips!.