When in squad, I would like to see a symbol on every character in squad that indicate whether the person is active or afk. My suggestion has two purposes. First, a person who need to afk will be shown as afk until they return. And second, a person who uses multi-clients and tries to afk through the entire run will be easily discovered.
Implementation of this would be really simple. Every window opened has an action called focus/unfocus so an active window is always focused, others are unfocused. If a window is unfocused (as in the case when you switch to another client which is on another window), show the afk-symbol adjacent to the character in squad. When the window is in focus again, remove/change the symbol.