Hi @saiergon - we've been encountering issues with socket.io and in most of the cases, there's an environmental factor, such as a firewall or proxy. The issue you encounter may or may not be a duplicate. For this reason it'd be best to file a github issue with all the possible details. The way to do that would be to first perform a completely vanilla setup and then gradually apply the changes toward the target environment, to inform us what exactly the root cause is.
Please include all the other details on the github issue, such as software versions and environment details.
Related info: due to encountering issues both with WebSockets and its fallback mechanisms in socket.io that constrain users with certain setup, and the limited need for socket-based communication, we're working on moving away from it.