Undoing security changes
If you have performed at least one security change, the "Undo last changes" menu item in the "Process" menu will be enabled.
This basically allows you to "undo" the last security change that you made, reverting it to the state
that the journal was in before your last processing. If you ever feel that you made a mistake by going all
friends only (or whatever), this allows you to correct that mistake. :)
Note: Completely refreshing your journal will erase your undo history.