I can drag and drop some existing email addresses from my address book into a new mailing group, but Firefox refuses to allow other email addresses to be dragged and dropped. It seems completely arbitrary as to which existing email accounts can be drag and dropped and which cannot. The online "HELP" instructions for this function are completely outdated, written for an earlier version of the software, and are no help at all. The whole process of creating a mailing group that has several (30-40 or more) existing email addresses in it is a giant task if one cannot drag and drop those into the group. It is as if whoever designed the mail group function did not expect anyone to set up anything but small groups. Please fix this function!! It's current usability is severely limited and a real pain to use.