As there can be any number of steps with the form, and an accidental refresh , reload or navigate away from the page could make it hectic for the user to start entering the form values again, so we have an option to save/restore the form by
enabling the option
enablePersistence in the main options, it provides you wiht the RESTORE button, through which you can restore the previous data for the un-saved form. The form fields are saved to the local storage as soon as you update or type in the fields.
The local storage would be cleared as soon as you submit the form or click the finish button. In this case, you would still see the Restore button but it will not restore any data.
The restore functionality is able to restore the dynamically created rows for the Tabular steps and the values for their fields.