Desktop file not copied during installation

As mentioned in this doc I have added a fontrapak.desktop and fontrapak.png file in folder snapcraft/gui and it is also copied in meta/gui of my snap, but a different system generated fontrapak.desktop is installed in /var/lib/snapd so the icon is not shown. How to ensure my .desktop is installed?

My snap is fontrapak .

I would suggest a ‘snapcraft clean’.