Catch page / browser reload (event ?)

Hi, my problem is about reloading the page on a refresh event (?) in perspective:

Is there any way to catch the refresh event from the browser or get the page-forward, page-backward event in perspective?

Many thanks in advance.

I think there is limited scope for this based on previous discussion in the forum.
What problem are you trying to solve?

I want to warn the user that he might lose his progress, for example:
->navigating views - which have no URL- in a page
->data that has not yet been saved.

The refresh event, even if you could catch it, would be too late. You should alter your workflow to save in session variables as you go, then provide a final step to save to permanent storage.