Jekyll generates closing tag for void element <source>

Jekyll generates closing tag for void elements which isn’t how it should be!

This:

<source src="{{ item.video }}" type="video/mp4" />

will generate:

<source src="/assets/uploads/my-video.mp4" type="video/mp4"></source>

How to change this?

Found the problem. It was the plugin ‘jekyll-loading-lazy’ that caused mayhem.