I’ve seen this issue crop up a couple of times here and there, so will offer what I think I know about it. Its a bit of a stinker though.
Short version:
The website owner has taken steps to prevent http://prophetie.rundertisch.at/ from being rendered in an iFrame on anything apart from on the site itself (SAMEORIGIN). This was achieved by the site owner by configuring X-Frame Options in their WebServer config.
Longer Version:
Chrome inspector tells us what has happened:
Thats the smoking gun. It’s telling us right there that the site has refused our request.
We can verify that the X-Frame Option is set by looking at the header in the network tools:
You can find out more about X-Frame options and how they can be implemented here:-
Feeling brave and not ready to give up? Well, there do seem to be some possible work arounds depending on how deep you are prepared to go. This one caught my eye:
https://blog.elev.io/getting-around-the-x-frame-options-to-sameorigin-issue/
Best of luck!