yanzar

Jan, sorry for referring to the apparently solved problem. But I have inserted your code into the child functions.php , but it does not work. What can be wrong?

<?php
add_action( 'wp_enqueue_scripts', 'theme_enqueue_styles' );
function theme_enqueue_styles() {
    wp_enqueue_style( 'parent-style', get_template_directory_uri() . '/style.css' );

}

function twentysixteen_post_thumbnail() {
	if ( post_password_required() || is_attachment() || ! has_post_thumbnail() ) {
		return;
	}

	if ( is_singular() ) :
	?>

	<div class="post-thumbnail">
		<?php the_post_thumbnail( 'full' ); ?>
	</div><!-- .post-thumbnail -->

	<?php else : ?>

	<a>" aria-hidden="true">
		<?php the_post_thumbnail( 'full', array( 'alt' => the_title_attribute( 'echo=0' ) ) ); ?>
	</a>

	<?php endif; // End is_singular()
}

?>

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