SunSpider is a JavaScript benchmark, probably one of the oldest ones around. We ran version 1.0.2, the latest and last version released (Sunspider is no longer maintained).
For this benchmark, a lower number is better.
Chrome started off OK:
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Firefox did worse:
Edge destroyed them both, finishing in less than half the time:
This is an old test, but the reason I keep running it is because I find it interesting that all three browsers bring in consistently worse results as time goes on. The placement has stayed the same lately though: Edge wins by a wide margin, followed by Firefox, and then Chrome.