Server is literally

# FastApi code

# cors
app.add_middleware(
  CORSMiddleware,
  allow_origins=["*"],
  allow_credentials=True,
  allow_methods=["*"],
  allow_headers=["*"],
)

Everything works fine from curl, and i even have cli-app that also has no issues with requests, but when i try to perform same request from browser, it fails…

function loadFsLayer() {

    const reqUrl = window.SERVER_RAW_URL + "/get-fs-layer"

    const reqBody = {
      layer: fsPath,
    }

    const reqOptions: RequestInit = {
      method: "POST",
      body: JSON.stringify(reqBody),
      headers: {
        'Content-Type': 'application/json',
        accept: 'application/json',
      },
    }

    // make request
    fetch(reqUrl, reqOptions)
    .then(async (res) => {
      const resData = await res.json()


      if (res.ok) {
        // if ok
        setRequestStatus(ReqStatusValues.success)
        setFsLayer(resData.layer)

      } else {
        // if server handled error
        setRequestStatus(ReqStatusValues.error)
        setRequestError(resData.error)
      }
    })
    // if not server handled error
    .catch((err: Error) => {
      setRequestStatus(ReqStatusValues.error)
      setRequestError(err.message)
    })

  }

this function results with net::ERR_NAME_NOT_RESOLVED

Googling it leads to “set cors on server” or “use proxy”, but… cors are set? Why it still getting errors?