As you might have already noticed, Facebook has secretly slid in a new comment system on the social network that takes the submit comment button out of the equation. Under the new system, to submit a comment the user just has to hit 'enter' on the keyboard. Previously when you hit enter, a new line started and to submit a comment a button had to be click.
The new system has got mixed reactions till now. While under the new system editing your already submitted comments is now possible, many users still prefer the old system, wherein pressing 'enter' will start a new line (opposed to pressing 'Shift+Enter' on the new system) and to submit a comment the submit button has to be clicked.
Get the old system back
In today's world, enjoying both sides of a coin is not a big deal. If you're happy with the new system implemented by Mark Zuckerberg and Co., you can continue as is. But if want to switch back to the old button-clicking system, there is a Greasemonkey script available for that.
(Related Entry: How To: Get the old Facebook Photo Viewing back)
Here’s a preview after installing the script:
Via Sum Tips