It's often futile to complain about Facebook changing. However, sometimes I can't help but have a moan.
Facebook recently changed their comments system, and it's irritated me more than any other change. The new concept that you can simply press Enter to post your comment, has led to many a deleted comment, or hasty explanation. I know I could press shift+enter but it just doesn't feel right.
For me, comments are for reasoned and considered responses, which often involve using paragraphs, or line breaks, sometimes for comic effect. Pressing enter to send makes perfect sense within the context of Facebook chat, but not comments.