I have created a page where i use the iframe widget. I use modeler 6.10 and when I run the app local it shows the page nicely (just a simple URL http://www.45fresh.nl) but when i run the app in the cloud the Iframe is empty and doesn't show at all ???
What is you Console printing? (F12)
I think it's an httpS mendixapp is loading a http website. Protocols should be the same. that's the reason it works local at http://localhost