When you create a new page you can enter web-links, or direct it to videos saved on your server.  Those files and/or links auto play, despite having autoplay=0, or autoplay=false or not having autoplay at all.

How can you stop it?

Nevermind

figured it out

<video width="320" height="240" controls> <source src="videos/example.mp4((video Directory / Video name))" type="video/mp4((Use your Video format))"> </video>

Example;