> querySelector with an id selector does in fact benefit from the id hashtable
Looking at the microbenchmark again, for Gecko, getElementById is around 300x
faster than querySelector('#id'), and even getElementsByClassName is faster
than it. It doesn't look like it benefits much from an eagerly populated hash
table?
P.S it's very interesting to see Gecko is around 100x faster than others when
it comes to the performance of getElementById. It probably does something
unusual?
