If this page won't load inside an iframe, the site may block embedding (X-Frame-Options / CSP).
Try a different URL, or host an internal page that allows embedding.
Tip: you can set URLs via querystring: ?f1=https://...&f2=https://...&f3=https://...&f4=https://...&f5=https://...
If you control the framed app, ensure it does not send X-Frame-Options: DENY/SAMEORIGIN.
For local testing, you can run: python -m http.server 8000 then open http://localhost:8000