I am also having the issue with remote users connecting to the server. Server status on the LAN is fine and users can connect. External users can't even get server status to spite having the port forwarding rules set to allow tcp/udp 19132. I also set ufw allow rules on the ubuntu firewall. So it looks like this is an issue with both windows and linux.
UPDATE
New server version fixed connectivity problems for me with external users...They can now connect remotely.
Please close the issue...was able to connect via UDP on the local network.
Why UDP? The java version uses TCP as you can see in the port listing.
confirmed on Linux Ubuntu 23.10 if you disable ipv6 in grub or kernel, it breaks the server.