Is there a way to massage the state in history mode?

[wanderley]

I am developing a game and I allow one of my cards to be "live" (:live? true in my data) which means that the clock ticks every few mileseconds. This causes a problem in history mode, because navigating to the previous state would turn :live? on what mutates the state right after I navigate one step on the past. I would like to set this flag to false either when I am in history mode or when it is saving the snapshots.