My react app uses axios for POST-requests to the server. When the server needs more than 2min for answering the request is called again. But only in FF, Chrome, NOT in IE11. I don't think that this is a Cross-Origin Resource Sharing (CORS) preflight issue, because this happens only for requests with long response times.
Client:
axios.post("host:port/context", {
params,
headers: {
"Content-Type": "text/plain"
}
});
Server:
const server = http.createServer();
server.listen(4000);
server.setTimeout(240000);
server.keepAliveTimeout = 240000;
A Router from express is also used on the server:
const router = new Router();
router.post(
"/context",
handlingOfRequest()
);