chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageView.java has the following:


    static String getTitleForDisplay(String title, String url) {
        if (TextUtils.isEmpty(title) && url != null) {
            Uri uri = Uri.parse(url);
            String host = uri.getHost();
            String path = uri.getPath();
            if (host == null) host = "";
            if (TextUtils.isEmpty(path) || path.equals("/")) path = "";
            title = host + path;
        }
        return title;


If |url| passed to the function has punycode-ecnode domain names, it'll be shown without being converted to Unicode. On other platforms, IDNToUnicode() is used to convert punycode/ACE IDN to Unicode IDN. 

This will only happen when a page missing <title> or non-HTML page is visited often and is featured in NTP AND has an IDN. The chance is very low. So, the priority is set to 3.