GNOME Files: Where are "Networks" cached?

Question

So, on this Ubuntu 18.04 box* running Files 3.26.4 under Other Locations I have this entry for a long gone Brother printing station thing:

Since it is clearly gone, there is no sensible way of interaction, so I wondered where this might be cached and how to remove it. Unfortunately, I could not find any documentation on this anywhere and searching for the raw string in gconf-editor, dconf-editor and recursively grepping .config also did not bring up any hits.

So, the question is: Where are the entries under "Network" in GNOME Files 3.26.4 saved/cached?

(*The author is aware of the outdatedness of this OS.)

Edit: The printer was never installed on this machine, so this cannot be a remnant of some driver installation.

Answer 1

They are not cached by GNOME; the corresponding GVfs providers all take their data "live" from external sources. There are several sources that network:/// gets its data from – look at the internal GVfs path names to get hints:

gio list network:///

This will show the 'raw' item name, such as dnssd-something, and will reveal it as originating either from DNS-SD (aka Bonjour, aka mDNS, discovered via avahi-daemon) or from SMB (more accurately NetBIOS, discovered via Samba)... or perhaps from Google Cloud Print, which GNOME used to integrate with.

If the result is DNS-SD, the data was received from avahi-daemon, which has no persistent cache; any ghost entries should disappear after restarting the service. Try avahi-browse, or the graphical avahi-discover, and/or Wireshark or tcpdump to figure out what's producing the service advertisements. (Use the capture filter port 5353.)