-        post = compat_urllib_parse.urlencode(data)
-        headers = {
-            b'Content-Type': b'application/x-www-form-urlencoded',
-        }
-        req = compat_urllib_request.Request(url, post, headers)
-        webpage = self._download_webpage(
-            req, video_id, note='Downloading video page ...')
+        error = self._search_regex(
+            r'class="err">([^<]+)<', orig_webpage, 'error', default=None)
+        if error:
+            raise ExtractorError(
+                '%s returned error: %s' % (self.IE_NAME, error), expected=True)
+
+        builtin_url = self._search_regex(
+            r'<iframe[^>]+src=(["\'])(?P<url>.+?/builtin-.+?)\1',
+            orig_webpage, 'builtin URL', default=None, group='url')
+
+        if builtin_url:
+            req = sanitized_Request(builtin_url)
+            req.add_header('Referer', url)
+            webpage = self._download_webpage(req, video_id, 'Downloading builtin page')
+            title = self._og_search_title(orig_webpage).strip()
+            description = self._og_search_description(orig_webpage).strip()
+        else:
+            fields = re.findall(r'type="hidden" name="(.+?)"\s* value="?(.+?)">', orig_webpage)
+            data = dict(fields)
+
+            post = compat_urllib_parse.urlencode(data)
+            headers = {
+                b'Content-Type': b'application/x-www-form-urlencoded',
+            }
+            req = sanitized_Request(url, post, headers)
+            webpage = self._download_webpage(
+                req, video_id, note='Downloading video page ...')