Added in 1.5

/debug [-ceinpt] [N] [on | off | @window | filename] [identifier]

Outputs raw server messages, both incoming and outgoing, to a debug.log file, or a custom @window.

If a custom window is defined, and it doesn't exist, a window will be created.

Switches

-c - Closes the associated custom window. (used with off)
-e - Adds extended debug information.
-i - Calls the specified identifier before a debug line is logged. The return value of the identifier is used as the debug line.
-n - Minimizes the custom window, if a new one is created.
-p - TODO
-t - Adds timestamp to the debug line.