Voice specifically blocks browsers from including pages in an iframe on a different domain - this is pretty standard good security practice these days, and prevents sites from spoofing another site by hosting content from one site under a different domain name.

There are some cases on the web where it is specifically allowed (e.g., a tool that lets you embed a calendar on your site or something). But for the most part, sites tend to block their content being used in iframes.

Usually there are better options than embedding content from one site directly into another. What is it that you are trying to achieve?

Thanks

Joe