zlacker

Or, one of the developers of the library saw it, decided to fix it in their spare time (does that exist at Apple?) before it became a bigger thing.

If not, talk about coincident that someone reported an issue and all of that you mentioned was already done before that happened, and the only thing missing was merging the code to the repository which was done after the issue was reported. Not unheard of, but feels less unlikely than "Engineer decided to fix it".