Related Posts: only enable on all singular views in block themes (#39784

)

Fixes #39783

This is a follow-up to #39730. Instead of enabling related posts in all singular views for every theme, keep relying on the `jetpack_relatedposts_filter_enabled_for_request` filter to enable theme in classic themes. Block themes will get them for every singular view by default, but classic themes will continue to only get them only for posts.

projects/plugins/jetpack/changelog/update-related-posts-availability-singular-views

@@ -0,0 +1,4 @@
+Significance: patch
+Type: other
+
+Related Posts: refine how related posts are made available on singular views in block themes.

projects/plugins/jetpack/modules/related-posts/jetpack-related-posts.php

@@ -1883,12 +1883,20 @@ protected function log_click( $post_id, $to_post_id, $link_position ) { // phpcs
 	/**
 	 * Determines if the current post is able to use related posts.
 	 *
-	 * @since 14.0 Checks for singular instead of single to allow usage on non-posts CPTs.
+	 * @since 14.0 Checks for singular instead of single to allow usage on non-posts CPTs in block themes.
 	 * @uses self::get_options, is_admin, is_singular, apply_filters
 	 * @return bool
 	 */
 	protected function enabled_for_request() {
-		$enabled = is_singular()
+		/*
+		 * On block themes, allow usage on any singular view (post, page, CPT).
+		 * On classic themes, only allow usage on single posts by default.
+		 */
+		$enabled_on_singular_views = wp_is_block_theme()
+			? is_singular()
+			: is_single();
+
+		$enabled = $enabled_on_singular_views
 			&& ! is_attachment()
 			&& ! is_admin()
 			&& ! is_embed()