[chrismorgan]

I’m surprised by the apparent magnitude of the difference between Firefox and Chrome. On my laptop I’m getting results roughly twice as fast as reported in the article, but still fairly similar ratios all round:

Firefox 96 (Nightly): document.getElementById 2–4ms avg 3ms, document.querySelector 25–27ms avg 27ms.

Chromium 96 (stable): document.getElementById 11–37ms avg 19ms, document.querySelector 86–155ms avg 101ms.

I’m also a touch surprised by the difference between getElementById and querySelector, because I vaguely recall querySelector being optimised in browsers for the ID case some years back so that there was negligible difference.

(P.S. seeing Firefox’s version number continuing to creep up on Chromium’s, soon to overtake, I wish browsers would scrap their version numbering systems and switch to YYYY.MM instead, or even YYMM like Windows if they want just one number. Can’t even claim user-agent sniffing hazards any more since they’re slightly killing those off and reaching three digits is going to cause some trouble anyway.)

[ehsankia]

As mentioned elsewhere, this is probably not testing what it thinks it is. The benchmark is doing a bunch of weird things, using timers that are not very precise, throwing away the first results, using template literals, etc. The results should be taken with a grain of salt.