Forget the above, I was wrong.  "guix pack" works well with regard to finding
the correct executable, with or without graft (could be wrong again, but so far
it seems to work).

The issue is that "next" cannot send XML-RPC requests to "next-gtk-webkit".  It
keeps polling it, but nothing flows through.

"next-gtk-webkit" seems to be working well however, the port 8081 is correctly
open.

I really wonder why the "next" executable fails to communicate with 8081.  

Question: Is there some network limitations when running a relocated "guix pack"?

-- 
Pierre Neidhardt
https://ambrevar.xyz/