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Youtube lagging...

AD3L1N
AD3L1N
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When i watch a video in 480p its lagging pretty bad on youtube... but i have no problem watching a stream in 1080p60fps... and i also notice that my cpu its going on 100% on youtube but i have no problem on other sites...

When i watch a video in 480p its lagging pretty bad on youtube... but i have no problem watching a stream in 1080p60fps... and i also notice that my cpu its going on 100% on youtube but i have no problem on other sites...

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jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Just to verify that your Firefox can handle all the YouTube formats (setting aside the question of speed), do you have blue checkmark boxes for the six test boxes on this page:

https://www.youtube.com/html5

Many users report that their computers have no problem when YouTube serves H.264-encoded video, but their CPU gets very busy when YouTube serves VP9-encoded video. You can check the encoding in real time if you right-click the video and choose "Stats for nerds".

I don't know what causes it, but one workaround for that issue is this extension: https://addons.mozilla.org/firefox/addon/h264ify/