data-background-opacity wrong doc

[feroda]

The doc of the data-background-opacity attribute in https://revealjs.com/backgrounds/#video-backgrounds is wrong.
The behaviour in my FF is that opacity = 1 is trasparent. Tested it with:

<section data-background-video="https://static.slid.es/site/homepage/v1/homepage-video-editor.mp4" 
        data-background-video-loop data-background-video-muted data-background-opacity="0">
<h2>Video</h2>                                                    
</section>

[chrisladams]

I'm actually not getting any reaction to using data-background-opacity="0.5" It shows opaque no matter what value I give.

[squareclouds]

strange, in my case images and videos work just fine in all tests (quite a few desktop and mobile browsers), also in vertical slides