Update: This extension has been removed from the Chrome Webstore by its author. We apologize for the inconvenience. There is still an alternative, you can use BirthdayFB which serves the same purpose and is much better as your friends would not know that you posted on their wall with the help of this app. Thanks Sean!
HappyBirthday Extension for Chrome has customizable options for wishing your Facebook friends. It needs access to your Facebook feed to build a list of birthdays and later, it posts wishes on their wall on their birthday.
These are the default options. You can customize the wishes that must be posted on your friends’ wall. You can also add new wishes to the list.
Once the wishes are sent, you are notified about it in the taskbar.
You can see the result on your friend’s Facebook wall to confirm that the wishes have been sent!
This extension seems to be useful when you have a huge number of friends on Facebook and wishing everyone manually becomes inconvenient!
Install HappyBirthday Extension for Chrome