This command causes the output screen to split, displaying the scrollback buffer. Text from the MUD continues to be received, and triggers continue to execute, however, the screen does not scroll. If value is 0, the screen is unsplit, otherwise the screen is split. If value is omitted, the current split state is toggled. This command is the same as pressing Control-Z, selecting Freeze from the Window menu, or clicking in the lower right corner of the output window next to the scroll bars.