Related posts lists gets inserted into html header tag

I’m having this weird issue where if our posts are short (like one or two sentence) the list of related posts gets inserted into the html header tag and displayed at the top of our website. It goes away if I insert a bunch of html non-breaking spaces… (And then I use an inline style tag to hide it with display:none…)

Help?

Thanks

https://wordpress.org/plugins/yet-another-related-posts-plugin/