Ticket #42910: 42910.patch

wp-admin/post.php

@@ -88 +88 @@
 
                 $_POST['comment_status'] = get_default_comment_status( $post->post_type );
                 $_POST['ping_status']    = get_default_comment_status( $post->post_type, 'pingback' );
+                if ( current_theme_supports( 'post-formats' ) && post_type_supports( $post->post_type, 'post-formats' ) && get_option( 'default_post_format' ) )
+                        $_POST['post_format']    = get_option( 'default_post_format' );
 
                 edit_post();
                 wp_dashboard_quick_press();