Save data for non-logged in users

Hi there,
I have a multi-step form on my client site, the content of the form is saved from one step to the other, everything works fine here.

The issue is, if the user refreshes the page, all the data from the fields is gone.
I know the option save drafts,just for logged in users, but what about non-logged?
Is there a way for the browser to remember the user data?

Thanks
Miquel