Fix #8592: Include private pages in parent dropdown for users with read_private_posts capability

Author: Vedanshmini26

src/wp-admin/includes/class-wp-posts-list-table.php

@@ -1885,6 +1885,10 @@ public function inline_edit() {
 								'sort_column'       => 'menu_order, post_title',
 							);
 
+							if ( current_user_can( $post_type_object->cap->read_private_posts ) ) {
+								$dropdown_args['post_status'] = array( 'publish', 'private' );
+							}
+
 							if ( $bulk ) {
 								$dropdown_args['show_option_no_change'] = __( '— No Change —' );
 								$dropdown_args['id']                    = 'bulk_edit_post_parent';

src/wp-admin/includes/meta-boxes.php

@@ -1012,6 +1012,11 @@ function page_attributes_meta_box( $post ) {
 			'echo'             => 0,
 		);
 
+		$post_type_object = get_post_type_object( $post->post_type );
+		if ( current_user_can( $post_type_object->cap->read_private_posts ) ) {
+			$dropdown_args['post_status'] = array( 'publish', 'private' );
+		}
+
 		/**
 		 * Filters the arguments used to generate a Pages drop-down element.
 		 *