The mod Kuxynator's Smart Linked Chests (3.0.16) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Kux-SmartLinkedChests::on_gui_opened (ID 95)
Kux-SmartLinkedChests/modules/ChestGui.lua:251: Data for link_id 847510061 not found
stack traceback:
[C]: in function 'error'
Kux-SmartLinkedChests/modules/ChestGui.lua:251: in function 'fnc'
Kux-CoreLib/lib/EventDistributor.lua:156: in function <Kux-CoreLib/lib/EventDistributor.lua:150>

I need more information. the more the better.

What are the circumstances?
Can this be reproduced?
Can you provide the save game?

I figured it out, sorry for bothering.
It was happening during set up process, when I set up recipe in assembling machine, then put down chests and inserters. Then copy-pasted needed materials in chests, and when I click on the output chest to set up final product in it I get this error.
It was because of other mod (Linked chest and linked pipe). I was going to use linked pipes from that mod, but whatever, I'll stick to barrels then.
Who would have thought that two linked chest mods do not get along, duh :D
Anyway, thanks for reply!

Who would have thought that two linked chest mods do not get along, duh :D

hmm shouldn't really happen because each chest entity uses its own IDs
but I have to admit I haven't tested this very intensively either

regarding linked pipes: I am working on a mod ‘solidified fluids’ so that you no longer need pipes.
i have startet a new game with spage-age to test this out.
https://mods.factorio.com/mod/Kux-SolidifiedFluids

Oh, so nice! Thanks a lot! Such a useful mod with your chests. It is perfect