I have experienced a bug in the current stable 44.6 version in the login. When logging in, I enter my username, and then go down to the password field. However, focus changes to both fields, so when I enter my password, it shows in the username field as well. The inverse does not happen, however. There are no error messages in the console, I'm running powder game on intel Snow Leopard.
Normal entry, only username entered:

Normal entry, both username and password entered.

This is a potential security risk, as it is likely that the username is not handled as securely as the password, along with the fact that onlookers can glean it from the user.