minor - retry login should retain username
if you fail to authenticate because of bad username and/or password, it would be nice if when you got to try again the username field was filled in with the username you last attempted to use.
if you are like me and you have enormously wide thumbs ("murderer's thumbs"), then it takes several tries to enter your password.
https://en.wikipedia.org/wiki/Murderer%27s_thumb
(from redmine: created on 2013-07-30, closed on 2013-08-13)