У вашего броузера проблема в совместимости с HTML5
Repositorio: https://github.com/IvanAquino/Ionic-Auth-Starter-with-Laravel-Passport
En este video podremos observar como conectar una app de ionic con autenticación en laravel usando passport
Enlaces
https://laravel.com/docs/5.6/passport
https://github.com/barryvdh/laravel-cors
https://ionicframework.com/docs/storage
https://ionicframework.com/docs/components/#segment