Force Media Web Part to use HTML5 version

Question

Is it possible to force the media web part to use the HTML5 version and never use the Silverlight version?

I've embedded videos to a page, and about ten minutes after I embedded them, the media web part would only load the Silverlight version. Most of our users will be on Chrome or Firefox, so using Silverlight isn't an option.

If it's not possible to force the media web part to use HTML5, is there a workaround?

I tried inserting a script:

<video poster="/path/to/SiteAssets/file/poster.png" width="320" height="200" controls="true">
  <source src="/path/to/SiteAssets/file/video.mp4">
</video>

But the controls don't fully load. Only the play button shows, it's grayed out, and the video won't play. I tested the code on a new html file to make sure I had it correct, and it functioned fine in that.

I haven't added any custom Javascript libraries (like jQuery) to my SharePoint site. I'm trying to avoid making any modifications to SharePoint's code, but if it's not possible to embed a video with the <video> tag by conventional means, then I'm willing to do it.

Edit: I forgot to mention that I'm on SharePoint Online.

Edit #2: After reading this question and top answer: How to implement HTML5 Video in Sharepoint 2010? I checked to see if my SharePoint site was loading HTML5 or HTML4. It's loading XHTML 1. That would explain why the <video> tag is not working. I'm going to research if there are any negative side effects of switching SharePoint to HTML5, but I think that's the route I'll go. I tried adding the XHTML definition to my sample HTML file and the <video> tag loaded fine. So I know it's possible to use it in SharePoint Online, it's just not working for some reason.

Answer 1

I've contacted Microsoft's support and they said it is not possible to force a media web part to use the HTML5 version.

Instead of inserting the videos directly on that page, I created thumbnail links to videos on the Videos section of Office 365. So on SharePoint, there would be little pictures of each video, and clicking on a picture would open a new tab to the video hosted in Videos. It's not a perfect solution, but it'll work for now.