On tab select, the URL is updated.

IPython/frontend/html/notebook/static/js/projectdashboardmain.js

@@ -15,6 +15,10 b' $(document).ready(function () {'
     IPython.page = new IPython.Page();
 
     $('div#tabs').tabs();
+    $('div#tabs').on('tabsselect', function (event, ui) {
+        var new_url = $('body').data('baseProjectUrl') + '#' + ui.panel.id;
+        window.history.replaceState({}, '', new_url);
+    });
     $('div#main_app').addClass('border-box-sizing ui-widget');
     $('div#notebooks_toolbar').addClass('ui-widget ui-helper-clearfix');    
     $('#new_notebook').button().click(function (e) {