On the right side of your topic, under 'See also', there is a link to 'Addressing an Email' that explains the Contacts sidebar.

Sorry no idea what you mean. What Topic?

I am Surprised no one has come up with an answer to this problem!!!! It makes Firefox useless.

Your topic is this webpage where you post questions and replies.

Thanks found it but nothing under See Also answers my question / problem.

The OLD version of Thunderbird had three boxes at bottom of address book contacts; Add To, Add to CC, Add to BCC

All versions have the Contacts sidebar with the three buttons. It is explained in the support article.

No, there are only three DOTS, right click on them but still NO option to send via cc or bcc. AND there are NO three dots against each entry / person within any of the address book "folders / list".

Screen Grab edited to show the Problem.

In latest version of Thunderbird, when sending an e-mail to several people I now can't select various address books and select the contacts I want to send to, and then choose to send to them via CC or BCC

In the compse window, click F9 or do View > Contacts Sidebar. Everything you want is there.

Great. Pity there is no mention of using F9. I spent ages trying everything from a logical view point. Thanks for that Wayne. Regards John.

The support article I cited in a previous reply includes this:

"The Write window offers a miniature address book pane called “Contacts Sidebar”. This is convenient and powerful especially for adding several recipients based on your search words. Select a specific address book to display only the contacts contained therein. You can show or hide this pane with the shortcut key F9 or using the menu: View > Toolbars > Contacts Sidebar."

Thanks for that. The confusing bit is that the Address Book is listed under TOOLS so you click the address book expecting everything to be there. So the address book or contacts, what ever you want to call it, is in fact split under two headings TOOLS and VIEW, not tidy is it!!!

Thanks again for you help. John.