Tobys

For anyone curious, this is the solution I came up with. If anyone can spot weaknesses or a better solution, then please let me know.

<?php
use Yoast\WP\SEO\Presenters\Abstract_Indexable_Presenter;

function remove_wp_seo_presenters( $filter ) {

	if (($key = array_search('Yoast\WP\SEO\Presenters\Open_Graph\Article_Modified_Time_Presenter', $filter)) !== false) {
		unset($filter[$key]);
	}

	return $filter;
}
add_filter( 'wpseo_frontend_presenter_classes', 'remove_wp_seo_presenters' );

class Custom_Presenter extends Abstract_Indexable_Presenter {

	public $property;
	public $content;

	function __construct($property, $content) {
		$this->property = $property;
		$this->content = $content;
	}

	public function present() {
		return '<meta property="' . esc_attr( $this->property ) . '" content="' . esc_attr( $this->content ) . '" />';
	}

	public function get() {
		return null;
	}
}

function add_custom_presenter( $presenters ) {

	$modified_time = new Custom_Presenter("article:modified_time", "2020-11-10");

	$presenters[] = $modified_time;

	return $presenters;
}
add_filter( 'wpseo_frontend_presenters', 'add_custom_presenter' );
?>

If you delete reCAPTACHA prepare for a TON of spam!!!

I switched to another form solution – SO happy!

Sorry for late answer, replys went to my spam mail.

I am using a dedicated VPS hosting, I have other WordPress sites that are working fine. Latest version of PHP 7.2

Lol I just found the error:

I used wpseo_metakey instead of wpseo_metadesc