This is not about browsers I tested below specifically... Feel free to post your own tests on any pair or more browsers!

So, because of some stuff going around Firefox, I had a chance to try out chromium-based Brave browser and did a few tests.

One interesting thing I found out was that futuremark browser test was [url=https://imgur.com/a/DuAbV]noticeably faster on Brave than Firefox ESR, especially when it comes to canvas rendering. The part of the test where description said "it pretty taxing for most machines" went absolutely fluid in Brave, but it was visually around 5 fps in Firefox. However, Brave failed on WebGL test.

Now, I was watching some of Fallout 4 play-through videos in Firefox and it came to my attention that it takes about 1 second to pause a playing video. I opened the same link in Brave and not only the pause/resume was being much faster - the FPS in the video itself was clearly much more sharp. I have no idea how to explain this, its like in Firefox its been rendered at 15 fps real, and it Brave at whole 30 (or 25?).

Previously I did not use Chrome or Chromium, or anything non-Firefox - but the difference here is pretty remarkable!..

Thats interesting, with CanvasMark Firefox outperformed Brave by big amount!

However, that fact didn't make real-world videos or text scrolling more responsible on Firefox.

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This is also an interesting testcase! It locks up one core to 100% on my xeon, and rest of them to about another 50-100% combined. So 150-200% in firefox ESR.

However in Brave, CPU cores idle at 5%.....

Stats just taken with htop. Can use any cpu monitoring tool.