How to disable AV1 support in Safari ?

Hi there ShinnySky,

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We hope that helps!

It's only true for old videos. Apparently they switched to AV1 completely, check out this one for example - all the resolutions are served in AV1 (if using Chrome): https://www.youtube.com/watch?v=WuljKartv2U

Please provide a link to the YouTube video that is playing in Safari in AV1.

Currently YouTube only pushes the AV1 codec to 8K HDR videos in Chrome.

av01 = AV1 codec

avc1 = H.264 AVC codec

YouTube is using H.264 in your case.

Please provide your Mac Model to know if your computer supports hardware accelerated video playback.

On my M1 MacBook Air I only get VP9 from youtube, if the video was posted recently, both Safari 16 and 17 (Technology Preview). At the same time Chrome gets same videos in AV1

Correct, Chrome supports the newer and more advanced AV1 codec while VP9 is used for Safari.

yep, if your browser supports it (Chrome), all current and future YouTube uploads are transcoded to AV1 since it saves YouTube/Google on bandwidth and storage costs compared to VP9.