Krita appimage ui scaling

Hi, I posted this question on ask.krita.org but got not answer so far.
I am using Krita on a 24 inch full HD screen and the fonts in the menus are quite small. Apparenty, checking the hidpi option in the Krita settings does not do anything. Using the latest appimage version of Krita on MX. The latest deb-package for MX is 3. Does anybody happen to know something here about this?

Thanks in advance and happy 2019!

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