Ticket #53813: 53813.diff

src/wp-admin/edit-form-blocks.php

@@ -77 +77 @@
  * Assign initial edits, if applicable. These are not initially assigned to the persisted post,
  * but should be included in its save payload.
  */
-$initial_edits = null;
+$initial_edits = array();
 $is_new_post   = false;
 if ( 'auto-draft' === $post->post_status ) {
         $is_new_post = true;
         // Override "(Auto Draft)" new post default title with empty string, or filtered value.
-        $initial_edits = array(
-                'title'   => $post->post_title,
-                'content' => $post->post_content,
-                'excerpt' => $post->post_excerpt,
-        );
+        if ( post_type_supports( $post->post_type, 'title' ) ) {
+                $initial_edits['title'] = $post->post_title;
+        }
+
+        if ( post_type_supports( $post->post_type, 'content' ) ) {
+                $initial_edits['content'] = $post->post_content;
+        }
+
+        if ( post_type_supports( $post->post_type, 'excerpt' ) ) {
+                $initial_edits['excerpt'] = $post->post_excerpt;
+        }
+
 }
 
 // Preload server-registered block schemas.