Ticket #32996: 32996.patch

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

@@ -887 +887 @@
                 $columns = $this->get_columns();
                 $default = $this->get_default_primary_column_name();
 
+                // If the primary column doesn't exist fall back to the
+                // first non-checkbox column.
+                if ( ! isset( $columns[ $default ] ) ) {
+                        $default = WP_List_Table::get_default_primary_column_name();
+                }
+
                 /**
                  * Filter the name of the primary column for the current list table.
                  *

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

@@ -1069 +1069 @@
          * @return string Name of the default primary column, in this case, 'title'.
          */
         protected function get_default_primary_column_name() {
-                return( 'title' );
+                return 'title';
         }
 
         /**