Replacing Oxygene theme by Plastique would be a workaround for this bug, but you then encounter another bug, even more annoying, this one:
https://bugs.kde.org/show_bug.cgi?id=178322
I didn't test the other themes. Oxygene is the default theme, so it absolutely has to work. I agree with Jithin Emmanuel and am very angry against Kubuntu team.
Replacing Oxygene theme by Plastique would be a workaround for this bug, but you then encounter another bug, even more annoying, this one:
https:/ /bugs.kde. org/show_ bug.cgi? id=178322
I didn't test the other themes. Oxygene is the default theme, so it absolutely has to work. I agree with Jithin Emmanuel and am very angry against Kubuntu team.