Invalid value in field "itemtype"

Hi there,

does it provide more info - such as the element that is invalid ?

Nothing specific. I added a link to Rich Results Test, maybe that can mean something to you.

Do you have any custom functions or elements that are adding Author meta to your site ?

Yes, I have the following snippets:

Snippet 1:

add_filter( 'author_link', 'my_author_link' );

function my_author_link() {
	return home_url( 'about' );
}

Snippet 2:

add_filter( 'generate_post_author', '__return_false' );
add_filter( 'generate_post_date_output', function( $date ) {
    printf( 
        '<span class="meta-gravatar">%s</span>',
        get_avatar( get_the_author_meta( 'ID' ) )
    );

    echo '<span class="meta-data">';

    printf( ' <span class="byline">%1$s</span>',
        sprintf( '<span class="author vcard" itemtype="httpss://schema.org/Person" itemscope="itemscope" itemprop="author"><a href="%1$s" title="%2$s" rel="author"><span class="author-name" itemprop="name">%3$s</span></a></span>',
            esc_url( get_author_posts_url( get_the_author_meta( 'ID' ) ) ),
            esc_attr( sprintf( __( 'View all posts by %s', 'generatepress' ), get_the_author() ) ),
            esc_html( get_the_author() )
        )
    );

    echo $date;

    echo '</span>';
} );

Snippet 3:

add_action( 'generate_after_entry_header', 'tu_page_meta' );
function tu_page_meta() {
	if ( 'page' == get_post_type() && ! is_page( array( 10, 15, 20 ) ) ) : ?>
		<div class="entry-meta">
			<?php generate_posted_on(); ?>
		</div><!-- .entry-meta -->
	<?php endif;
}

In Snippet 2 - see this line:

sprintf( '<span class="author vcard" itemtype="httpss://schema.org/Person" itemscope="itemscope" itemprop="author"><a href="%1$s" title="%2$s" rel="author"><span class="author-name" itemprop="name">%3$s</span></a></span>',

In there you see:

itemtype="httpss://schema.org/Person"

notice the https is incorrect, it has one too many s - change it to:

itemtype="https://schema.org/Person"

Yup that was the problem. Thank you David!

You're welcome