If you've noticed on twitter's website, the long links that you share get counted towards the 140 character limit in a different way.

How does twitter calculate the long links towards 140 character quota?

They will count every link shared to be 20(21 for https) characters. So, it does not matter what the length of the link you are sharing is, it gets counted as 20 characters only.

Starting today, you will see the exact same behavior on Buffr as well. So go ahead, no more need to shorten URLs when you share them via buffr.