This happens only if you are next to the sign when you click it. Don't need to be walking. This appears to be if you click or right click on your own player character rather than related to the signs.
This is probably because clicking on a sign or right clicking another player opens the sign dialogue or Trade/Party/Clan dialogue.
Might be a client side bug related to GUI when trying to interact with yourself instead of a sign or different player.
This happens only if you are next to the sign when you click it. Don't need to be walking. This appears to be if you click or right click on your own player character rather than related to the signs.
This is probably because clicking on a sign or right clicking another player opens the sign dialogue or Trade/Party/Clan dialogue.
Might be a client side bug related to GUI when trying to interact with yourself instead of a sign or different player.