[Feature] Prevent autoplay - inform user about browser function

[ganego]

I have been using your userscript for quite a while now in one browser and in this one, the YT video was paused when opening it and just showing the thumbnail and player - which I liked.
I now installed your script in another browser and the video always autoplayed - despite the 'autoplay' button from YT in their player being on the 'pause' setting.
I was looking through the addon's settings and was quite confused why such an extensive YT enhancement addon did not have an option to stop autoplay. It took me a while to realize that it's actually Firefox preventing YT's autoplay and not your addon.

There is no need to add a 'stop autoplay' feature to your addon when the browser can do that itself, but I propose to add an option for it anyway that will then open a little help text (or a link to the documentation) to tell the user how they can achive this in their browser.