Why is request made by AP.require('request') cancelled in chrome

[Artur Kruk]

Hi,

In the app I am working on I need to upload attachments.

In order to do that  I use `/rest/api/2/issue/{issueIdOrKey}/attachments`.

Following code works on all browsers except chrome.

function uploadAttachments(issueId, files) {
    return new Promise((resolve, reject) => {
        AP.require('request', function (request) {
            request({
                url: `/rest/api/2/issue/${issueId}/attachments`,
                type: 'POST',
                contentType: 'multipart/form-data',
                data: {'file': files[0]},
                success: (responseText, responseStatusText, response) => {
                    if (response.status === 404) {
                        return reject(response);
                    }
                    try {
                        let payload = /\S/.test(responseText) ? JSON.parse(responseText) : null;
                        return resolve(payload);
                    } catch (error) {
                        return reject(error);
                    }
                },
                error: function (error) {
                    reject(error);
                }
            });
        });
    });
}

Unfortunately, chrome cancels this request.

My question is

What are the probable causes of request cancellation, and how could I resolve this issue?