Inactive Players

This is a small small question. I know that after 2 days of no activity a player is listed as inactive. I know that they can come back to the game, but will their icon switch back to an active player when they log back in? I know pretty well when the AI does something, but I would just like the know if a player comes back online if it's them playing so I can take them seriously. Otherwise I know it's one infantry unit that keeps taking my provinces in this dominion game mode (which is absolute chaos btw).