CORS POST never occurs, even with successful OPTIONS preflight.

I have the following set up to POST to a different domain:

fetch(params.url, params.options)
  .then(this._errorHandler)
  .then(response => {
    statusCode = response.status;
    return response.json();
  })
  .then(result => {
    result.statusCode = statusCode;
    return Promise.resolve(result);
  });

where my options look like:

{
  body: JSON.stringify(requestBody),
  credentials: 'same-origin',
  mode: 'cors',
  headers: {'Accept': 'application/json', 'Content-Type': 'application/json'},
  method: 'POST'
}

When I am creating a POST request (that requires CORS), the OPTIONS preflight returns as a 200 with the correct headers, but the fetch never actually does the POST request. Is there something I need to add to the options, or handle in another manner? I couldn’t find another issue or documentation related to this specific problem.

Edit: Yes, there is actually a properly set-up server with CORS enabled and working in other xhr requests.

[neurosnap]

Does the request go through or does it just not show up in Chrome’s dev tools? I’m having the same exact issue and found this chromium issue: https://bugs.chromium.org/p/chromium/issues/detail?id=457484

Basically all fetch API requests with preflight end up in the Network -> Other tab

[mistadikay]

Basically all fetch API requests with preflight end up in the Network -> Other tab

it was exactly the case for me in Chrome 🙈