Greasy Fork

a very good tool for youtube music, only missing the ability to make songs play only audio
other than that its great

Thanks for the feedback :)
I've just released version 2.0.0 and it has a feature that allows you to automatically or manually place the video's thumbnail over it.
Note that this will not save bandwidth as the video will still keep playing in the background, but hidden.
Unfortunately there is no way to change the way that works so this is the best that I can offer.