This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Wannan tattunawa ta zama daɗaɗɗiya. Yi sabuwar tambaya idan ka na bukatar taimako.

Youtube lagging...

more options

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...

All Replies (1)

more options

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/