Changing default icon

Is the desktop icon like this-
image
what is referred to by this-
image
If so, why am I still getting the generic nsb icon?

Is this for a PWA or a VoltBuilder app?

VoltBuilder

Have you supplied icons (and splash) in the VoltBuilder section of Project Properties?

Nope. I had the icon in the ‘common’ section of properties.
Problem solved. Thank you.