diff --git a/src/wp-content/themes/twentytwentyone/image.php b/src/wp-content/themes/twentytwentyone/image.php
index e5ebfba33d..c691e18594 100644
--- a/src/wp-content/themes/twentytwentyone/image.php
+++ b/src/wp-content/themes/twentytwentyone/image.php
@@ -99,7 +99,7 @@ while ( have_posts() ) {
 			}
 			?>
 		</footer><!-- .entry-footer -->
-	</article><!-- #post-## -->
+	</article><!-- #post-<?php the_ID(); ?> -->
 	<?php
 	// If comments are open or there is at least one comment, load up the comment template.
 	if ( comments_open() || get_comments_number() ) {
diff --git a/src/wp-content/themes/twentytwentyone/template-parts/content/content-single.php b/src/wp-content/themes/twentytwentyone/template-parts/content/content-single.php
index f6c97c9ca5..14ddb0f0c4 100644
--- a/src/wp-content/themes/twentytwentyone/template-parts/content/content-single.php
+++ b/src/wp-content/themes/twentytwentyone/template-parts/content/content-single.php
@@ -41,4 +41,4 @@
 		<?php get_template_part( 'template-parts/post/author-bio' ); ?>
 	<?php endif; ?>
 
-</article><!-- #post-${ID} -->
+</article><!-- #post-<?php the_ID(); ?> -->
diff --git a/src/wp-content/themes/twentytwentyone/template-parts/content/content.php b/src/wp-content/themes/twentytwentyone/template-parts/content/content.php
index 309f0bbeb6..0ee7d628ed 100644
--- a/src/wp-content/themes/twentytwentyone/template-parts/content/content.php
+++ b/src/wp-content/themes/twentytwentyone/template-parts/content/content.php
@@ -43,4 +43,4 @@
 	<footer class="entry-footer default-max-width">
 		<?php twenty_twenty_one_entry_meta_footer(); ?>
 	</footer><!-- .entry-footer -->
-</article><!-- #post-${ID} -->
+</article><!-- #post-<?php the_ID(); ?> -->