hello,

Go to Address Book >> select the list and click on Properties or right click and select Properties just erase the name of the contact of the list and click on OK

regards, gautam sharma.

That did not work. I am on a Macintosh. I can't right click. This address is frozen in the address book with no way to edit or delete it!

I have no idea what "frozen" means.

Double clicking the contact or selecting the contact and clicking the Properties button opens the edit dialog box just like a right click does. You can do those on a Mac. Selecting the contact and pressing the Delete button on your keyboard will delete the contact after confirming the dialog box.

https://support.mozilla.org/en-US/questions/990940

https://support.mozilla.org/en-US/questions/996474