Comment # 3 on bug 1128397 from Damian Zar��ba

(In reply to Fabian Vogt from comment #2)
> That's not Qt scaling - it's the font dpi autodetection.
> 
> To disable that, force the font dpi to 96, either by using the configuration
> offered by your DE (xfce has it, not sure about others), run "echo Xft.dpi:
> 96 | xrdb -nocpp -merge" or set "QT_FONT_DPI=96".

It works with only laptop screen, I need to test it with second screen
attached. Forcing DPI in MATE don't want to work, I need to use _QT_FONT_DPI=96
to have it working, so It's time to make simple killqtscaling.sh in
/etc/profile.d/