Which Lua functions and Lua features are not implemented with CORE?

Which functions and features are not implemented with CORE ?

So far I learned

Some of Lua's standard functions have been removed in Core.So if you for example have access to the io library you're not running your script from within Core.

Lua in Core does not support "dofile()" or "loadfile". For "require()", our implementation differs slightly from vanilla Lua. Instead of giving it a script or file name, you give it a script ID, so you'll want a custom parameter that's an asset reference pointing at the script you want to "require()".

Btw, there is a wonderful open-source community project with an example how to do require() on CORE:

No access to the operating system by "os()", especially no execution of commandline tools of the operating system.
No access to command line arguments ( "arg" ), as Lua scripts are not called by commandline.
No global "debug".

explaining the CORE specific "context" by a code example, to execute functions in other files. So this is not Lua standard, right?!

What about access to internal global Lua tables, which is widely used by standard Lua applications?
What is missing there?

What else ?
Please let us collect in this thread what you experienced ?