Making the iTerm2 color tab labels on activity more useful


In using iTerm2, I frequently see tabs turning a different color, and just assumed that this was because of new output in that window. The help was no good, as I couldn't find a decent word to search for, but after combing through the preferences, I discovered that this was because "Color tab labels on activity" was selected.

Ok, so far so good. I would like to use this feature for a tab that has a chat window in it. The problem is, I frequently see tabs change color but when I go to that window there is no visible change in the output. Sometimes the color changes in a tab that has nothing but an idle command prompt; in that case I can't image there would even be some kind of invisible change like spaces or something being output.

Is there some way I can actually make use of this feature? As it is, it is pretty useless if 90% of the time when I go to the tab to see what happened, nothing happened.