+/**
+ * Displays error message
+ *
+ * Since 1.4.1 function checks if page header is already displayed.
+ * Since 1.4.3 and 1.5.1 function contains error_box hook.
+ * Use plain_error_message() and make sure that page header is created,
+ * if you want compatibility with 1.4.0 and older.
+ * @param string $string
+ * @param array $color
+ * @since 1.3.2
+ */