Prepopulate username field on web app login pages
Often I need to access several web apps running on the same hostname, with different usernames. For example, I might need to access webmail, phpMyAdmin, and a wiki all on https://dev.example.com/. For convenience, I usually save the login details in the web browser, but if there are multiple different usernames on the same host then the browser doesn’t know which one to automatically populate into the login field. However, if each login page itself prepopulates the username, then the browser is then able to prepopulate the saved password as well.