If you try entering in a reply here on Answers, and leave the page without submitting (or try to refresh the page without submitting) then you get a warning like so:
I however do not get that on Laserfiche Forms. I would like this functionality though as it appears some of our clients have been experiencing situations in which the screen appears to refresh somehow while they are filling in a form. While we cannot tell for sure if this is a Laserfiche issue or a workstation issue, this functionality would be helpful in reducing the opportunity for the form to suddenly blank itself unless the user actually intended to do so.