Use Arcade and domain description in pop-ups

Hi all

I want to use Arcade to compile 2 attributes from the same featureclass.

Is there a way to display domain description rather than domain value in Geocortex?

I have made the expression below and tested it in AGO Web Map and here the description is shown. When I transfer the expression to Geocortex Essentials, but it does not show anything in the viewer pop-up.

var KONarmatur = $feature.konventionelArmatur;

var LEDarmatur = $feature.LEDArmatur;

var lystype = IIf(KONarmatur == 102, DomainName($feature,"LEDLys"), (IIf(KONarmatur == 0, DomainName($feature,"LEDLys"), DomainName($feature,"konventionelLys"))));

return lystype

How should an expression look like?

Thanks