After restarting the server, signs cannot be edited.

Steps to Reproduce:

1. Place a sign.
2. Attempt to edit the sign by right-clicking on it (editing works as expected).
3. Restart the server.
4. Try to edit the sign by right-clicking on it (the sign editing interface does not appear, and you are unable to edit the sign).

 
If a sign has not been edited, you can open the interface. However, once the interface is opened, you will be unable to edit that particular side after the next server restart.
 
This problem is impacting both classic and hanging sign.