Streamlit apps iframing don't work since the migration on subdomains-based URL structure

Thanks for reporting the issue, @Alekseo! :pray:

I’m pasting @randyzwitch’s answer here, for visibility.

Hi Alexis -

This was a bug that escaped, not a specifically intended feature release. It has since been rolled back, and I’m clarifying with our product and eng teams about pre-announcing any breaking changes so there aren’t issues like this in the future

Best wishes,
Charly