Change external-appstream-urls from a GSetting to a system configuration file
It’s weird that the external-appstream-urls
GSetting, which is set by a user, can then download and cache appstream files for the whole system, affecting all users.
I think external-appstream-urls
should be changed so that it only downloads and caches appstreams for the current user (i.e. as if external-appstream-system-wide
were always false). And a new system configuration file should be added which specifies which appstream URLs to download system-wide (if any).
The new configuration file would be {/run,/etc,/usr/local/share,/usr/share}/gnome-software/appstreams.conf
, loading whichever one is found first, as is the standard for other similar configuration files.