Searching for update shows these results:
https://docs.python.org/3.13/search.html?q=update
The search result list includes frozenset.update, which is false: frozenset does not have such method.
I guess this is due to the fact that on the target page https://docs.python.org/3.13/library/stdtypes.html#frozenset.update, set and frozenset are explained together, but the search indexer doesn't catch it.
#frozenset.update is even the working page anchor, while #set.update is not. More confusion.
Further, I'm guessing that this will be happening with more class groups documented together.
Linked PRs