The game will frequently randomly freeze for approximately 21 seconds or even more in some rare cases before the game returns to normal. During the freeze the server is still running and any actions that occur during the freeze will all play out quickly. The best way to reproduce this effect is by creating a new world and exploring your surroundings, it should freeze for approximately 21 seconds. The game will also freeze when exiting the settings menu, also for approximately 21 seconds, this will also happen every time you close the settings. The bug can occur in Singleplayer, Multiplayer, and featured servers.