Mail - the tick box to show all member addresses
Despite not ticking the box to show all member addresses in Mail's Composing preferences they do show when I send an email - how can I fix this? It has annoyed me for years - I do not wish to use blind copy as I want the recipient to know that I have copied the email
iMac (Retina 5K, 27-inch, Late 2014)
3.5 GHz Intel Core i5
32 GB 1600 MHz DDR3
High Sierra 10.13.4
Mail Version 11.3 (3445.6.18)
Mac mini (Late 2012), OS X Mavericks (10.9.1)