YouTube vp9 vs AVC cpu usage

[Atak_Snajpera]

Is This normal that vp9 is less cpu intensive during decoding than older avc?

Browser: FireFox 53
GPU: ancient Radeon 1950 so no hardware decoding

AVC 1920x1080@60fps drops frames like crazy while vp9 is smooth
http://i.cubeupload.com/scaKSt.png

VP9
http://i.cubeupload.com/VBbJZn.png

[hello_hello]

I've not investigated which types of video are effected, but apparently lots of people have issues with the html player and excessive CPU usage.

I think I did a while back, which would be why I installed the YouTube Flash Video Player plugin (https://addons.mozilla.org/en-us/firefox/addon/youtube-flash-video-player/) (I think CPU usage was my problem but I installed the plugin a fair while ago).

I don't frequent YouTube much but I haven't had any issues with the plugin that I know of, except sometimes when a page loads there's a message in the video area complaining about playback not being supported for my device, or something to that effect, but it goes away quickly and then the video loads and plays normally.