If the current box has a slug encoding last time’s adjustments, then this command undoes the adjustments. Example: If the adjustment changed 12-point text to 12.567-point text, then this command will find any 12.567-point text and change it to 12-point.

This is independent of the usual undo mechanism. For example, a user can fit the text to the box, then fix a couple of typos, and then ask for the fitting to be undone. This will undo the fitting without losing the typo fixes.