No, they don't. I have to type it out in full each time. Do I need to register or something? This is a great website. I've been doing the guardian crossword for 35 years, this will be such a help as I reach my dotage!
Tilly, you don't have to register and there is no moderation. Or rules. Your username/email address not coming up with a single keystroke may be to do with the browser you use or how you have it configured.