Our company has been having this issue for several weeks now and we’re unable to solve it.
Some of the requests that are being made by the browser to our servers are returning access-control-allow-origin error. This error triggers randomly, and on random users’ computers. It is somewhat reproducible but it does not happen every time.
For example, it will make a request to the same end point, and one request will come back valid while the other request will come back with a CORS issue. This makes us certain that it is a cloudflare issue and not a server issue, since it works one second and the next it does not.