I am using Ubuntu 14.04 LTS with GNOME shell and from the list of "Add an Online Account", Twitter is missing. Below is a screenshot:

Any idea why?
I am using Ubuntu 14.04 LTS with GNOME shell and from the list of "Add an Online Account", Twitter is missing. Below is a screenshot:

Any idea why?
Try to reinstall account-plugin-twitter
sudo apt-get install account-plugin-twitter
Or you can try to install all account plugins:
sudo apt-get install account-plugin-*