The mod Reverse Factory caused a non-recoverable error.
Please report this error to the mod author.

Error while running event reverse-factory::on_tick(ID 0)
LuaEntity API call when LuaEntity was invalid.
stack traceback:
reverse-factory/control.lua:7: in function 'checkinvs'
reverse-factory/control.lua:80: in function
<reverse-factory/control.lua:76>
stack traceback:
[C]: in function 'index'
__reverse-factory/control.lua:7: in function 'checkinvs'
reverse-factory/control.lua:80: in function
<reverse-factory/control.lua.76>

I updated the mod and got this error when a construction robot upgraded from Reverse Factory 3 to Reverse Factory 4. I did not get the error when I manually upgraded it. The factories weren't doing anything when they were upgraded. It kicked me into the main menu.

Thank you for fixing the last bug, I found another lol

Lmao damnit. That's a weird one... I'll look into it =P

I got it; I'm not sure if this is new or a result of the upgrade planner in 0.17, but it seems I missed an event in control.lua, so it wasn't properly removing a recycler from the list of inventories to check for auto ingredient pushing. So it crashed when checking an entity which no longer existed.

Should be fixed as of v6.1.5

Thank you :D

Actually, looking back through my previous bug reports, it seems this error has been there for about a month or so, probably since they added the upgrade planner.

It's a very similar sounding error, just on different lines. Although since I added the new tiers of recyclers, I also had to add a few lines to this file, so it would make sense if it's the same error caused on a later line.

I'm just glad to finally have this resolved! You always seem to help me find and solve these longstanding issues, so thanks to you as well! :D