''<p>dforrest [[#question-1508152|said]]</p>'' <blockquote>Below is an archived response of how to add multiple recipients to an email being composed: ''I think the easiest way is, when you are in compose window, press F9 to bring up the address book in left column. You can tick the desired recipients and then click the Add button to place in To, CC, or BCC ''. My follow-up question is "how many recipients can be added to 'To' in any one email"? </blockquote> There is no limit in the RFC, but you may find your mail provider has a limit to prevent spam. Usually expressed as a number of emails per day/hour or the like. Each email address counts as an email for those type of things. SO if you address an email to 100 people and your provider limits you to 50 per hour, the mail will not send. BTW I think you forgot your link to the archived topic. Support document on addressing an email: https://support.mozilla.org/kb/addressing-email#w_adding-recipients-to-your-email-message