Workaround for Maya 2018 WPF sample not showing again after closing it

Having trouble with WPF sample in 2018 .net devkit?  It is reported that dagexplorer command won't reopen a closed window in Maya 2018. This could be fixed with following modification:

Replace

MGlobal.executeCommand($@"catch (showWindow ""{hostTitle}"");");

with

MGlobal.executeCommand($@"catch (workspaceControl -e -visible true ""{hostTitle}"");");

To make the window showing again.