diff --git a/idna/src/uts46.rs b/idna/src/uts46.rs
index ac348d1fa..32a4a8399 100644
--- a/idna/src/uts46.rs
+++ b/idna/src/uts46.rs
@@ -130,7 +130,7 @@ fn passes_bidi(label: &str, is_bidi_domain: bool) -> bool {
 
     match first_char_class {
         // LTR label
-        BidiClass::L => {
+        BidiClass::L | BidiClass::EN => {
             // Rule 5
             loop {
                 match chars.next() {
diff --git a/tests/unit.rs b/tests/unit.rs
index 62401c943..ad60b1411 100644
--- a/tests/unit.rs
+++ b/tests/unit.rs
@@ -226,6 +226,8 @@ fn test_idna() {
     assert!("http://goșu.ro".parse::<Url>().is_ok());
     assert_eq!(Url::parse("http://☃.net/").unwrap().host(), Some(Host::Domain("xn--n3h.net")));
     assert!("https://r2---sn-huoa-cvhl.googlevideo.com/crossdomain.xml".parse::<Url>().is_ok());
+    // https://github.com/servo/rust-url/issues/489
+    assert!("http://mail.163.com.xn----9mcjf9b4dbm09f.com/iloystgnjfrgthteawvo/indexx.php".parse::<Url>().is_ok());
 }
 
 #[test]