on default ubuntu installs /etc/environment only contains the PATH variable (on very old upgraded systems there might be a LANGUAGE/LANG one as well, but that was dropped at some point)
/etc/environment is only writable for the system admin (who would also be the one adding proxy info there) so i think it is safe to just include EnvironmentFile=/etc/environment by default in the snapd service file.
on default ubuntu installs /etc/environment only contains the PATH variable (on very old upgraded systems there might be a LANGUAGE/LANG one as well, but that was dropped at some point)
/etc/environment is only writable for the system admin (who would also be the one adding proxy info there) so i think it is safe to just include EnvironmentFile =/etc/environme nt by default in the snapd service file.