minetest errors

2022-07-26 13:48:28: ERROR[Main]: ModError: Failed to load and run script from /home/greeter/.minetest/mods/moretrees/init.lua:
2022-07-26 13:48:28: ERROR[Main]: /home/greeter/.minetest/mods/biome_lib/api.lua:36: attempt to concatenate local 'msg' (a table value)
2022-07-26 13:48:28: ERROR[Main]: stack traceback:
2022-07-26 13:48:28: ERROR[Main]: 	/home/greeter/.minetest/mods/biome_lib/api.lua:36: in function 'dbg'
2022-07-26 13:48:28: ERROR[Main]: 	/home/greeter/.minetest/mods/moretrees/saplings.lua:10: in main chunk
2022-07-26 13:48:28: ERROR[Main]: 	[C]: in function 'dofile'
2022-07-26 13:48:28: ERROR[Main]: 	/home/greeter/.minetest/mods/moretrees/init.lua:80: in main chunk