diff --git a/src/wp-includes/block-template.php b/src/wp-includes/block-template.php
index 7bd5684ed2..4d3a0449ea 100644
--- a/src/wp-includes/block-template.php
+++ b/src/wp-includes/block-template.php
@@ -312,6 +312,10 @@ function _block_template_render_without_post_block_context( $context ) {
  * @param WP_Query $wp_query Current WP_Query instance, passed by reference.
  */
 function _resolve_template_for_new_post( $wp_query ) {
+	if ( ! $wp_query->is_main_query() ) {
+		return;
+	}
+
 	remove_filter( 'pre_get_posts', '_resolve_template_for_new_post' );
 
 	// Pages.