The Safari extension is not working on my MacBook Pro as I have tried to make the extension work on the system. But is not happening and the system is also getting down due to that. The couch base code has to be changed and I have seen the ERROR CODE 0XC0000428 on the interface of the extension. I have also contacted https://errorcode0x.com/error-code-0xc0000428/
The ability to add window.safari into safari-extension URLs is something that we are currently investigating.
We can also take a look at the fact that these iframes aren't being injected into HTTPs pages. I believe it is a https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS