@mathio the code did the trick. thank you so much. 

Why can’t we have full-screen on mobile without a placeholder/welcome screen?

Hello @dsimsrb 

you can display standard embed on desktop and popup embed on mobile via custom code (CSS or JavaScript) if you want more customization. For further customization you can trigger the popup programmatically from any custom UI you might build.

By default, the placeholder welcome screen and its “start” button is used to trigger the modal.