Whenever the mod tries to load and is set to merge nullius chests, be that by selecting them in startup settings or with the all chests mod, I get this error:
Failed to load mods: WideChests/prototypes/entity.lua:31: attempt to index field '?' (a nil value) stack traceback:
WideChests/prototypes/entity.lua:31: in function < WideChests/prototypes/entity.lua:14 > (...tail calls...)
WideChests/prototypes/entity.lua:153: in main chunk [C] in function 'require'
WideChests/prototypes/data-updates.lua:4: in main chunk
I don't have any mods beyond those stated to be compatible with nullius, besides some UI and QOL mods.

Nullius renamed chest names couple of days back, I have made the necessary changes but I can't test it now. But you can get it from https://github.com/Atria1234/WideChests in the meanwhile, you can download the entire repository and rename some mod folder in the zip file and copy it to factorio mods.

I'll hopefully get to testing/releasing this soon

It worked! Thank you.