Page loaded over HTTPS but requested an insecure XMLHttpRequest endpoint
What I can do to fix this (other than installing a real SSL certificate).
You can't.
On an https webpage you can only make AJAX request to https webpage (With a certificate trusted by the browser, if you use a self-signed one, it will not work for your visitors)
I had the same issue for my angular project, then I make it work in Chrome by changing the setting. Go to Chrome setting -->site setting -->Insecure content --> click add button of allow, then add your domain name [*.]XXXX.biz
Now problem will be solved.
I solved the problem adding a slash at the end of the requesting url
This way: '/data/180/'instead of: '/data/180'