Feature: Warning popup when doctype is not yet save

[SanaullaHaq]

@doca

Warning prior to closing a document with unsaved changes. Ist it possible?

This can be achieved using onbeforeunload event - Prevent leaving the page using plain JavaScript

refresh: function(frm) {
        window.onbeforeunload = function() {
                if(frm.is_dirty()){ return 'A valid String';}
                else { return; }
        }
}