I have Azure function app written in python. App works in azure editor fine and in calling request from python also fine. But when I want to call it from client side javascript (from my react app) I get empty response

I call it in this way:

    fetch("https://xxxxx.azurewebsites.net/api/testtrigger?", {
        mode: 'no-cors',
        method: 'GET'
    }).then(response => response.text()).then((response) => {
        console.log(response)
    })

The no-cors is there because I test it on localhost.

Function code looks like this:

import logging

import azure.functions as func

def main(req: func.HttpRequest) -> func.HttpResponse:
    logging.info('Function called')
    return func.HttpResponse("Its working")

Azure shows that function is being called, but is there any reason I missed why this should't work? I receive response but its empty, here is response json:

     Response {type: 'opaque', url: '', redirected: false, status: 0, ok: false, …}
body: (...)bodyUsed: falseheaders: Headers[[Prototype]]: Headersappend: ƒ append()delete: ƒ delete()entries: ƒ entries()forEach: ƒ forEach()get: ƒ ()has: ƒ has()keys: ƒ keys()set: ƒ ()values: ƒ values()constructor: ƒ Headers()Symbol(Symbol.iterator): ƒ entries()Symbol(Symbol.toStringTag): "Headers"[[Prototype]]: Objectok: falseredirected: falsestatus: 0statusText: ""type: "opaque"url: ""[[Prototype]]: Response

This code in python works fine:

import requests
x = requests.get('https://xxxxx.azurewebsites.net/api/testtrigger')
print(x.text)