How to fix refused to connect when migrating from Yourls?

Question

PHP

Good afternoon.
I installed on Yourls cloud hosting. SSL certificate connected. The service itself is installed and works without problems. Short links generates. However, when I try to follow any of these links, I get the error "xx refused to connect.", where xxx is the domain where the landing page is located.
For example
https://grn.one/9dgr5 -> www.youtube.com refused to connect.
https://grn.one/osnxr -> github.com refused to connect.
https://grn.one/jbxzo -> www.energymadeeasy.gov.au refused to connect.
There was nothing complicated in the settings, especially since there are a large number of installation instructions on the network. And here on this error there was a problem with search of the information.

Answer 1

These sites do not allow themselves to be displayed in iframe
https://developer.mozilla.org/en-US/docs/Web/HTTP/...
Errors like "Refused to display in a frame because it set 'X-" are thrown in the browser console Frame-Options' to 'sameorigin'."