a call to get_webmention_form_text in p tags. get_webmention_form_text https://github.com/pfefferle/wordpress-webmention/blob/master/templates/webmention-comment-form.php calls wpautop, resulting in next p tags. [post with default webmetion form run through w3c validator](https://validator.w3.org/nu/?showsource=yes&showoutline=yes&showimagereport=yes&doc=https%3A%2F%2Fdougbeal.com%2F2018%2F07%2F15%2Ffeature-wordpress-rel-issues-link-in-plugin-generated-widget-when-in-debug-mode%2F#l149c36)