@aferlazzo Well, first you need to make sure you are not changing or refreshing the page when you submit the form: https://stackoverflow.com/questions/19454310/stop-form-refreshing-page-on-submit
If you do that then you can easily show a dialog or something if an input is invalid. The page transitions are controlled with
For the unformatted text, perhaps try using local dependencies so the CSS is loaded earlier. Otherwise, you will probably have a loading screen at the beginning of your app that will hide all the “set up”.