this is only speed controller that works for me on youtube without causing other issues. A+++

This extension is the update of the video speed controller and is really good.

Please come with android support

This is awesome!
Enables fine-grained change of the playback speed in all audio or video elements.
Improves the original plugin and does not break the onratechange event so it may be used by other scripts.

Great job done by M.A, it works perfectly in my FF while offering more advanced functions than the popular one. Just wanna say thank you!