Firefox saves a login (username and password) for a specific origin (protocol and hostname) and not for a full path on a server, so if you try to save a password for another path on the same server and have the same user name then only one password can be saved and you overwrite a previously saved password if that is what you try to do. *https://support.mozilla.org/en-US/kb/password-manager-remember-delete-edit-logins You can use "Create New Login" to add a new login manually. *https://support.mozilla.org/en-US/kb/add-login-firefox-password-manager