Most people want a notification when something is said on a channel they have joined, particularly if they have been addressed directly. There is a global minor mode that will do this kind of tracking for you. All you need to do is switch it on using M-x rcirc-track-minor-mode. To make this permanent, add the following to your init file:
(rcirc-track-minor-mode 1)
When other people say things in buffers that are currently buried (no window is showing them), the mode line will now show you the abbreviated channel or nick name. Use C-c C-SPC to switch to these buffers.
By default the channel names are abbreviated, set
rcirc-track-abbrevate-flag to a non-nil value. This might be
interesting if the IRC activities are not tracked in the mode line,
but somewhere else.
If you prefer not to load rcirc immediately, you can delay the
activation of this mode:
(add-hook 'rcirc-mode-hook
(lambda ()
(rcirc-track-minor-mode 1)))
If you’ve joined a very active support channel, tracking activity is no longer useful. The channel will be always active. Switching to active channels using C-c C-SPC no longer works as expected.
The solution is to mark this channel as a low priority channel. Use C-c C-l to make the current channel a low-priority channel. Low priority channels have the modeline indicator “LowPri”. C-c C-SPC will not switch to low priority channels unless you use the C-u prefix.
If you prefer a channel to never show up in the modeline, then you have to ignore it. Use C-c TAB to ignore the current channel.