Enable Iframe Embedding Workaround

I need a reliable way to embed the following URL inside an iframe on my own web page:

https://mo.gatsbykynurin.com/ixtpN1rMouCgbiXr/129820

My goal is straightforward: seamless embedding for a web page. Right now the site actively blocks iframing through JavaScript and likely by setting headers such as X-Frame-Options or Content-Security-Policy. I’m looking for a clean, maintainable workaround—whether that involves a server-side proxy, header manipulation, postMessage communication, or another secure technique that preserves full functionality of the original content for visitors.

Deliverables
• A working proof-of-concept page (HTML + any supporting files) that displays the link in an iframe without triggering the site’s anti-embed protections
• Clear, step-by-step setup instructions so I can replicate the solution on my own server and migrate it to production

Acceptance criteria
• The embedded content loads automatically in all modern browsers without console errors
• No visible changes or functional restrictions compared with visiting the URL directly
• Solution does not rely on browser extensions or manual user actions

If additional server configuration or a lightweight middleware service is required, please include sample code and the exact headers or rules that must be applied.