I have one issue below:
Mixed Content: The page at 'https://example.com' was loaded over HTTPS, but requested an insecure XMLHttpRequest endpoint 'http://api.example.com/api/demo.php'. This request has been blocked; the content must be served over HTTPS.
It's work fine when request from 'https://example.com' to 'http://api.example.com/api/demo.php'