Factorio version 2.1.23, mod 2.3.0

An issue occurred at placing the entity:

The mod Underground heat pipe forked (2.3.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event underground-heat-pipe-forked::on_built_entity (ID 6)
LuaEntity doesn't contain key neighbours.
stack traceback:
[C]: in function 'index'
__underground-heat-pipe-forked/control.lua:248: in function 'check_for_neighbours'
underground-heat-pipe-forked/control.lua:294: in function 'update_mode_for_all_pipe_to_grounds'
underground-heat-pipe-forked/control.lua:232: in function <underground-heat-pipe-forked/control.lua:199>

Thanks for the report. I will try to replicate the error and fix it within the next days.

Thanks for the fix, the underground pipes can be placed now. But they dont conduct heat, without error, just do nothing.

This is concerning, thanks for the report. I need some time for that as I am not the original author.