Hi,

I currently play with a modpack that allows for multiple player forces to exist and to join each other.
When 'game.merge_forces' is called by one of my mods, machine-upgrades crashes one tick after merge_forces is called with the following error:

The mod Machine Upgrades (0.69.16) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event machine-upgrades::on_nth_tick(1)
LuaForce API call when LuaForce was invalid.
stack traceback: [C]: in functionl _index' machine-upgrades_ _/script/beacon-manager.lua:94: in function 'update_all_entitv_moduling'
machine-upgrades_iscript/beacon-managerlua:169: in function 'handler'
machine-upgrades_ Jscript/event-lib.lua:155:
in function <__machine-upgrades_ Jscript/event-lib.lua:153> 

Thanks for the report. I know how to fix it, but I'd need to know which mod to test with to know if my fix is sufficient.

I just uploaded the fix, bundled with a different compat fix. I'm marking this as resolved unless otherwise stated.

Thank you, the fix worked.
The relevant mod is "Planetary Diplomacy".