function twenty_twenty_one_post_thumbnail() {
    if ( ! twenty_twenty_one_can_show_post_thumbnail() ) {
      return;
    }
    ?>

		<?php if ( is_singular() ) : ?>

			<figure class="post-thumbnail">
				<?php
        // Lazy-loading attributes should be skipped for thumbnails since they are immediately in the viewport.
        the_post_thumbnail( 'post-thumbnail', array( 'loading' => false ) );
        ?>
				<?php if ( wp_get_attachment_caption( get_post_thumbnail_id() ) ) : ?>
					<figcaption class="wp-caption-text"><?php echo wp_kses_post( wp_get_attachment_caption( get_post_thumbnail_id() ) ); ?></figcaption>
				<?php endif; ?>
			</figure><!-- .post-thumbnail -->

		<?php else : ?>

			<figure class="post-thumbnail">
				<a class="post-thumbnail-inner alignwide" href="<?php the_permalink(); ?>" aria-hidden="true" tabindex="-1">
					<?php the_post_thumbnail( 'post-thumbnail' ); ?>
				</a>
				<?php if ( wp_get_attachment_caption( get_post_thumbnail_id() ) ) : ?>
					<figcaption class="wp-caption-text"><?php echo wp_kses_post( wp_get_attachment_caption( get_post_thumbnail_id() ) ); ?></figcaption>
				<?php endif; ?>
			</figure><!-- .post-thumbnail -->

		<?php endif; ?>
		<?php
  }