[igouy]

Smalltalk stores:

memory snapshot "image"

AND "change log" text file

AND "sources" text file.

https://cuis-smalltalk.github.io/TheCuisBook/Code-Management...

If the "sources" file is missing the byte code will be decompiled to show class and method definitions, but the original names will be unknown.

[xkriva11]

It is only an implementation detail. It is a matter of change of a few methods only to store sources directly in methods. I tried that once.

[igouy]

It's all only "an implementation detail".

Some of them are documented and expected.