NiFi rest api creating parameter context

Hi,

I noticed that in NiFi rest api documentation for version 1.9.0 the parameter context endpoints have been removed, even though they existed in version 1.15.2

Furthermore, I am using NiFi version 1.13.2 and I can see that in my browser's debugging tools, in the network tab, whenever I create a parameter context, a post request is sent to 

http://localhost:8080/nifi-api/parameter-contexts:

 

and the following payload is being sent :

{
    "component": {
        "name": "aaaaaaaaaaa",
        "description": "aaaaaaaaaaaaaaaa",
        "parameters": []
    },
    "revision": {
        "clientId": "3d3697c2-017e-1000-0610-31b28073cf9b",
        "version": 0
    }
}

The parameter context is successfully created. However when I attempt to send a post request from an external API or even hit the previously mentioned endpoint through the browser using the same payload, I get:

HTTP 405 Method Not Allowed

 My questions are:

1. Is anyone aware whether these endpoints have been removed/restricted intentionally?

2. If they are not remove/restricted, has anyone been able to successfully send a post request and create a parameter context through NiFi's rest api?