I'm making a custom Rich Media creative (NOT with Google Web Designer), which plays a video on the background and some canvas animation on top of it.

When I upload the banner to DoubleClick it throws an error:

The following asset in the rich media ZIP contains at least one video src tag: . Ask your creative developer to use the Enabler API (Enabler.getUrl) to load the video.9093

Enabler's API says this function should provide a correct URL to the video (and it does, I checked), but how do I load the video with this URL not using src?

It looked like that:

<video id="video" preload="auto" muted poster="poster.jpg" src="video.mp4">

I removed the src from the video tag and added this code instead:

video = document.getElementById('video');
video.src = Enabler.getUrl('video.mp4'); 

Of course it didn't help as DoubleClick still sees video.src in this code and throws the same error.