Login: go insenstitive after 3 unsuccessful password attempts instead of just one
When you're logging in, if the user enters their password incorrectly, the entry becomes insensitive for a short period, forcing them to wait before they can try again. This is quite frustrating in situations when you mistype your password and, I think, is inferior to the behaviour that I've seen on other platforms.
The behaviour that we have in the latest designs for the login screen is to only make the entry insensitive after three unsuccessful attempts, but to make the period of insensitivity longer.