I thought that it was an interesting bug, since one change far away broke something which seemed largely unrelated, and even though the code is self-evidently wrong, it's still fairly difficult to find the bug if you don't have some hints.
This is almost ancient Greek for me.
I now do understand why people have been studying Computer Science for Years, and it is not possible to rely entirely on Chat GPT prompting like I usually do when dealing with code bugs.