Is there any working example of embedding iframe to a website, using nginx and jwt and enabled autologin?

The question is on above:

Is there any working example of embedding iframe to third party website and autologin?

I’m using nginx in between.

I’ve only found bits of information here and there and nothing complete with rigth kind of configurations.

Some websites claims that jwt authorization is possible, somebody here on this forum claims it’s not.

Somebody should make tutorial video about this.