18.04: "untrusted launcher" -- how to make it *permanently* trusted

[Robert Heller]

I recently upgraded a batch of diskless workstations to Ubuntu 14.04 using 
DRBL.  Everything is working well, except for one small problem:  We have some 
launcher files (.desktop) files in the login account Desktop folder, but even 
though they are chmod +x (and some are in fact direct copies from 
/usr/share/applications) they come up as "untrusted".  (And yes, they are 
properly owned by the user and group, etc.).  They work, once you click "Trust 
and execute", but they become untrusted again on reboot.

What is going on here?  Is there some additional magic needed somewhere?  Or 
is it just that with GNome 3 / Ubuntu 18.04 you just cannot have 
*applications* on the Desktop (everything *must* be in "favorites" or you must 
search for it everytime).

And no, SELinux is not running on the Ubuntu 18.04 machines, although SELinux 
is running on the (CentOS) file server for the /home file system, which is NFS 
mounted on the diskless workstations (is there some there that needs to be 
done?).

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Custom Software Services
http://www.deepsoft.com/  -- Linux Administration Services
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