To make the autoplay on html 5 elements work after the chrome 66 update you just need to add the muted
property to the video element.
So your current video HTML
<video
title="Advertisement"
webkit-playsinline="true"
playsinline="true"
style="background-color: rgb(0, 0, 0); position: absolute; width: 640px; height: 360px;"
src="http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.mp4"
autoplay=""></video>
Just needs muted="muted"
<video
title="Advertisement"
style="background-color: rgb(0, 0, 0); position: absolute; width: 640px; height: 360px;"
src="http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.mp4"
autoplay="true"
muted="muted"></video>
I believe the chrome 66 update is trying to stop tabs creating random noise on the users tabs. That’s why the muted property make the autoplay work again.