We are in the middle of an endless conversation* in the office :
Should undos have a timer before disappearance or should they be displayed until next action?
In our discussion, closing or changing pages is an action but clicking in white-space is not (this also can be debatable).
I am not going to beat about the bush: I am against the timer. I feel it is stressful and the time chosen is completely random. Every user can take her own time to read and execute things within the application. This does not prevent me from being open to discussion.
Gmail does have a timer in its optional undo for sending mail for instance :
This leads to my next question: if a timer is the best option, should the application display a countdown or not ?
Context:
Case 1: An accounting software for non accountants - like double entry bookkeeping for those who are interested, so it means undoing is kind of sacrilegious but a mistake is really bad and ugly. The action we are dealing with here is a new line in the book.
Case 2: A time-track workflow and the action we are dealing with is validating the calendar and sending it to the manager for validation. It does not have to be real time.
I know it is impossible to be in the middle of an endless conversation
Furthermore : Do you have any examples of undos message? Using a timer or not.