Comment 1 for bug 415484

related info from http://code.google.com/p/google-web-toolkit-incubator/wiki/LoginSecurityFAQ

Certain browsers offer the option to store username/password combinations so that they are automatically filled in for the user the next time they visit the page. However, usually this works only if there are two input boxes (one of type password), and only if those input boxes are loaded along with the main page, and not added later via javascript (which is what GWT does).

In order to force these input boxes to show up, stuff them in the project's HTML in an invisible div. Then, in GWT, instead of creating a TextBox and a PasswordTextBox, make the div visible and read out the values using the DOM. library.