Added in 1.5

/tab [[network] [#channel|nick]|N]

Activates the matching window or the window number counting from the top.

Parameters

[network] - $network to match.
[#channel|nick] - Channel or nick to match.
[N] - The Nth position.

Example

;Activate #channel window on $network NordicIRC.
/tab NordicIRC #channel

;Activate the 5th window.
/tab 5