Add extra check for tuple length to avoid out of range error in Frontend resolver (#66470)

homeassistant/components/frontend/__init__.py

@@ -533,6 +533,7 @@ class IndexView(web_urldispatcher.AbstractResource):
         """
         if (
             request.path != "/"
+            and len(request.url.parts) > 1
             and request.url.parts[1] not in self.hass.data[DATA_PANELS]
         ):
             return None, set()