I can't say I'm entirely happy with my result so far, but I have figured out the general thrust of this bug. Minetest seems incompatible with the libjsoncpp in Debian. Solving this issue properly may be a mess, but the proof for the location of the problem also suggests a temporary workaround.
If you have the Minetest source available (Upstream source -- "git://github.com/minetest/minetest"), it contains "src/json/". From within, you can simply "g++ -shared jsoncpp.cpp -o libjsoncpp.so.0" and use LD_LIBRARY_PATH to force the current Debian package to load that preferentially to the system-wide version. Suddenly, the server list and online mod repo work as they do upstream. An obvious temporary solution is to keep the bundled libjsoncpp, but a long-term solution will require figuring out why the system libjsoncpp fails and either making it work correctly or making Minetest use it correctly, dependent on which is behaving improperly. I haven't looked too deeply into which is responsible, though I'd suspect Minetest. I'll look into it later, but it is quite late right now, so I figured I'd send in what I have and get to bed. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org