Degradation/ without js unusable

Issue Summary

Hi,

i disabled js for some tests and this makes the module completely unusable. The login opened on a new page and when you imput you data you get a textfield with:

{ "status": true, "updaters": [ ], "debug": [ ], "messages_error": [ ], "messages_status": [ ], "messages_warning": [ ], "redirect": "http://192.168.1.238/WORKSPACE_DRUPAL/test_drupal/user/1?974634881=1", "preview": null, "form_id": "user_login", "options": { "enabled": true } }