Steps to repro: Open iMessage Click on one of your conversations Copy some text from your conversation Type the letters "test" into the message section Press the "return" button (adding a new line to the message) Now try and paste the text you just copied onto this line (press/hold for options). As you can see, you are unable to paste into the message. A workaround is to press the "return" key again and then select the empty line ONE ABOVE the last line in the message. You can now press/hold on this line and paste your message. BUG??