Using a semicolon ( ; ) in the server-name field causes clients to be unable to join the server. No feedback is provided in the console to indicate a problem.
- Open server.properties and change server-name to "Test;" without quotes
- Start the server
- Note no indication the server isn't or wont function
- Open Minecraft - note the server details is stuck on locating server
- Attempt to connect, note the immediate "Unable to Connect" screen
Some form of feedback to advise invalid characters in name.
Server starts without issue and appears to be working but no one can connect.