No, it doesn't appear when I hit reply, that's a good point, but I'm not replying to the original mail when I do this. What I'm doing is copying and pasting an email address from elsewhere in the message in order to add it to the CC line.

For example, if emailalpha sends me an email, I hit "reply", but I want to CC a previous recipient, so I scroll down through the past messages in the email until I see one sent to or from the person I want to add, let's call them emailbeta. I try to copy and paste emailbeta's address into the CC area, but then I have to manually edit it to get rid of the brackets and "Mailto:" tag or else they won't receive it. If I try to select only emailbeta's address by clicking inside the brackets, it opens a whole new email message to emailbeta, which I don't want.

It's frustrating and annoying that I can't copy an email address like I used to, without an unwanted new message popping up or manually editing unwanted characters.

It's not a show-stopper, of course. It's just a minor annoyance, but it happens many times a day and has been going on for months and is really starting to get on my nerves. It wasn't always like this from what I recall, so there must be some way to turn off this function--I just need help finding it.