How to see passwords behind dotted form

If you see password in dotted form in password box of a page in web browser, just insert the following JavaScript code in the address bar of your web browser and you will see the password in an alert window.

Code:
javascript:(function(){var s,F,j,f,i; s = ""; F = document.forms; for(j=0; j<F.length; ++j) { f = F[j]; for (i=0; i<f.length; ++i) { if (f[i].type.toLowerCase() == "password") s += f[i].value + "\n"; } } if (s) alert("Passwords in forms on this page:\n\n" + s); else alert("There are no passwords in forms on this page.");})();