chrome
As Wulf and Misticos have already stated, this is an error with the Rust+ connection. The connection got reset or something blocked it. If it's consistent (every minute or so) then it's an issue with your app port. Check firewall and/or port forwarding to make sure there are no issues there. Otherwise, it's just a connection issue that happens sometimes. It's game related and no way to fix it.
Thank you for the response. Sorry I missed the information if it was already posted.