Hi Janice, there are a few different ways that Firefox could remember your user name and enter it for you:

(1) Saved Login

Firefox's built-in password manager can fill many login forms. Do you use this feature? More info: Password Manager - Remember, delete and edit logins and passwords in Firefox.

(2) Form History

Usually you have to start typing a character or two before form history suggestions appear in a little drop-down below the field and you can select them there.

(3) Cookies

When you request your email web page, Firefox sends any cookies the site set on your last visit so the site can customize your experience. That may include the site showing you the login page with your user name filled in, or if you didn't sign out of your email after your last visit, resuming your existing session.

There are several ways that you can set Firefox to erase your cookies. Add-ons also may remove cookies. If you think this might be the situation, could you let us know:

(A) If you sign out of email, then immediately open a new tab and try to sign in, is the user name present at that point, or already missing?

If the username is present in (A), maybe it disappears when you close Firefox? Then we would suggest checking some settings related to what Firefox does when it closes.

Detail like websites remembering you and log you in automatically is stored in cookies, so make sure you aren't clearing important cookies.

You can use these steps to make a website recognize and remember you.

• create a cookie allow exception with the proper protocol (https:// or http://) to make a website remember you

You can check that you aren't clearing important cookies.

• using "Delete cookies and site data when Firefox is closed" keeps cookies with an allow exception
• using "Clear history when Firefox closes" to clear cookies clears all cookies including cookies with an allow exception you may want to keep
• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exceptions for passwords and other website specific data

• Settings -> Privacy & Security
  Cookies and Site Data: "Manage Exceptions"