Come on, "not publicly available"? You know how git works right? Each Claude release probably has the HEAD of main compiled as "1.4.0" until there is a real official release.
If you can't find an update at that place in the codebase saying 1.4.0 you can ask where it is. It seems after doing that and not receiving an answer would be the appropriate time to start making the claims that people are throwing around.
This seems like a candidate
https://github.com/oven-sh/bun/commit/b18bf6d1d0a92238f240bf...