I've had this problem too, though this time the log in worked first time.
Noticed exactly same behavior, but I always type my log in manually.
During times when the problem happened, my packet logs show the user name being sent with the password field blank/empty even though the password was definitely typed in on the screen. from the dedicated log in screen, either clicked from the index page or after the the failure takes you to the special log in screen, logging in works every time.
I never reported this because RJ asked for people to hold off on reporting problems and I was waiting to see if either the problem cleared up or RJ asked for remaining issues to be reported...
Separately, how about a secure https log in option?
Or maybe implement "HTTPS Everywhere" You are not allowed to view links.
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