No cut and paste. Drag and drop contacts between books. If you want to have a contact in more than one book you can copy instead of move by holding the control key while drag and drop. You will see a plus sign appear beside the contact to indicate a copy.

OK, that element seems to have worked. Rather cumbersome, since there are about 2,500 entries in the whole system. Please furnish the direct link to the place in the general instructions where this is explained - there are other things about this which I'll want to see about. In particular, is there a way to open the addressbook in a spreadsheet, to use the sort-function?

Open address book. From the Menu Bar select Tools-Export Select file type comma separated You can open a CSV file in Excel.

Holding the control key to copy instead of move is standard computer operation. When moving files in windows if you drag between different drives, it assumes you want to copy. If you drag between folders on the same drive it assumes move. Holding the control key reverses these actions.

You do know that you can use other standard computer operations to select multiple contacts to move or copy?

cntrl+a = select all

click a contact, move up or down several contacts and hold the shift key while clicking that contact = first and last contact clicked on and all in between are selected

hold the control key while clicking random contacts = select any contact clicked on

hold the control key when clicking on a selected contact = deselect that contact

Air - I know all of that about select-copy. I've been doing programming since 1966 - writing code on the IBM 1629 and 1130.

Lemme go look at ... Tools-Export Select file type comma separated You can open a CSV file in Excel. ... to see if it opens the addressbooks.

Air - I know all of that about select-copy. I've been doing programming since 1966 - writing code on the IBM 1629 and 1130.

Not trying to insult your computer skills but I am not a mind reader.

Final step, please. (I'm writing before I go try it:) With the multiple, categorized spreadsheets, I will need to know the steps (and locations) to save the new addressbooks so that the Thunderbird app will pick them up. I assume that I can put them in linked, working mode, then delete the now-superfluous BIG staring books.

Can you refer me to the weblink for the instructions on this (and the related activities.)

Merry Christmas!  :-)

You assume incorrectly.

You can not import to the address book the completed CSV files.

Or as you are a programmer you can code something to convert your CSV files into Thunderbird native MORK format. See https://developer.mozilla.org/en/docs/Mork_Structure and https://wiki.mozilla.org/Mork

This add-on will import MORK files to the address book. https://freeshell.de//~kaosmos/morecols-en.html