lxqt not showing application in full screen

Hi
I have AM335x starter kit with 4.3" resistive touch screen and recently ported Debain 9.1 for beagalebone. Everything works fine but whatever application I open in desktop shows only upper section and bottom section always remain out of window

So I am wondering is it due to resolution/size of screen that is not configured or is this behavior native to lxqt desktop

it looks like the 4.3 lcd size got passed thru what ever sharing software
you are using..

Regards,

its realVNC, LCD screen display same way.