[louzell]

This has not been my experience at all. I was compelled to use Chrome at my last job (there was a bunch of internal tooling built around Chrome assumptions). I was there for almost five years, so I did a whole lot more than kicked the tires. My daily driver has remained FF, and I have not perceived any noticeable difference in perf because of it.

[fooker]

I tried Firefox a few weeks ago on a 2015 MBP plugged into a 4K tv, it could basically not play any high res video at any watchable framerate. Safari did the best, Chrome was close.

[nateb2022]

See https://bugzilla.mozilla.org/show_bug.cgi?id=1716164

My guess is that Firefox was being served AV1 by YouTube. Intel chips prior to 11th gen have no hardware decode support for AV1, and so your CPU was overworked and bottlenecking.

Chrome and Safari probably resorted to H.261/H.263/H.264 encoded video from YouTube, and relied on the hardware decoder.

Easy fix: go to `about:config` and disable `media.av1.enabled`.

[mrguyorama]

I also had a 2015 MBP and watched 4k video on it basically every day. I have no idea what you experienced.

[fooker]

That's exactly how software bugs work, weird setup specific issues that are expensive to triage and fix.

But if you are not convinced see how many others have this issue by googling "site:reddit.com firefox stuttering on 4k video on mac"