In the basic HTML version of Gmail, if you go to compose a message, and start typing the person's name in the To: field, an autocomplete list comes up. Enter, space, and tab don't seem to make it accept the currently selected autocomplete entry. Is there no way to do it from the keyboard? The only way I seem to be able to get it to work is by clicking the entry with the mouse.
This is on Chrome for Win7, even.