Sure, here is one of my guesses, though the site is actually pretty complicated, so this is a very simplistic reason as an example. Assuming they use a static site generator. Each Article is it’s own WYSIWYG. They have a special document format that allows for inline notation of annotations. Someone was editing the doument to update an annotation, they left out a closing bracket and the SSG just decides to not render invalid annotations, so everything after the missed closed bracket was assumed to be bad data.