Still not fully working for me as of today (Wednesday Feb 12). Went to book a ticket using Firefox on my Mac. It would display the fares correctly, but when I went to the booking page and tried to log in, it wouldn't let me. Nor would it let me log in when I went back to the homepage and tried to log in there with the idea of then re-trying the booking.
Did eventually work on Firefox on my PC, though. And then they had the temerity to ask me to fill out a survey about the quality of my online experience!