How to proxy a third party iframe link?

Question

Nginx

The iframe makes my head swell. Help plz advice.

There is a link to someone else's iframe (video player). You need to inject your styles into this iframe. Previously, it seemed to be possible to do this, but now nothing works and I can not find the reason. Most likely the reason is CORS (which is strange, because a couple of weeks ago everything was working in the test).

Got a question. Can I https://example.com/embed/157298proxy a view's iframe link through my nginx? Well, i.e. the link on the client will be like https://example.myserver.com/embed/157298, and nginx is already requesting the original. If so, what header settings should be set correctly? Host, frame opshins, some special ones for proxies, etc.?