I unmarked kmix volume feedback because I use keyboard shortcut to change volume and don't want this feedback to pop-up when I for example watch something.

But Plasma 5 doesn't respect this setting. After every volume change with keyboard shortcut the pop-up appears.

https://docs.kde.org/stable5/en/kdemult ... eneral.png

Do you have the same? Is it Plasma 5 bug or something Manjaro specific?

It is on Manjaro, Plasma 5.13.4.
I also have problem with other settings that Plasma don't respect. Is it Manjaro bug or general Plasma bug?