[mibbitier]

This is a horrible misfeature.

Often, I select bits of an email, to copy and paste elsewhere to check things. Then I hit reply, and wonder why only the currently selected text is there.

There should be a way to turn this "feature" off.

[jemka]

Thunderbird does the same thing and I agree with you. I've learned to just hit reply, then edit.

[vvhn]

mail.app on OS X also does this ( can be turned off i think ) and its always a similar annoyance to me ( select something to copy paste and the reply only has that)

[r00fus]

At the very least, when you select text it should allow you to "Reply to Selection" as an option in the reply button (perhaps as default). I leave it to the UI experts to determine what's default and wording/icon changes. This meta-mode shouldn't reuse the reply keybinding either, and use a new one.

This would be far more discoverable and only minor changes to documentation over the current approach.

[oftenwrong]

It should also probably be documented.