Works great for my purposes. I'm able to follow a LinkedIn Learning course thanks to the app. The presenter goes way too fast. LinkedIn allows 50% speed, but that's too slow. 80-90% is super helpful. I had to increase the opacity on the controls to see them when I press "V". The UI isn't super slick, but it's well thought out.

I've set left and right arrow keys to skip videos for 5 secs, but skip forward button skips the videos 30 secs.

Wish there was a way to set up additional keys, for example Ctrl+Scrollwheel Up/Down

The functionality of the plug-in is great, but performance is unfortunately awful.

Admittedly I am a person that regularly has over 30 tabs open at once, and noticed Firefox's general performance drop when open for long periods of time to the point of requiring regular browser restarts.

I've had no performance issues after disabling the extension, so unfortunately will give it a low rating.

Feels exactly like the Chrome one which I've been using for about 5 years.