Runtime error from mod '*builtin*' in callback on_shutdown(): /usr/local/share/minetest/builtin/game/forceloading.lua:82: attempt to index local 'f' (a nil value)
stack traceback:
	/usr/local/share/minetest/builtin/game/forceloading.lua:82: in function 'write_file'
	/usr/local/share/minetest/builtin/game/forceloading.lua:99: in function </usr/local/share/minetest/builtin/game/forceloading.lua:98>
	/usr/local/share/minetest/builtin/game/register.lua:412: in function </usr/local/share/minetest/builtin/game/register.lua:392>