After the 'twitpocalypse' the twitter plugin (an extremely popular and visible plugin) for GNOME Do is entirely broken. This is dude to integer overflow in twitter post ids, and has a simple fix of using a long instead of an int for the post id.
Reproducing this bug is very simple, try to post anything to twitter from GNOME Do.
1. sudo aptitude install gnome-do gnome-do-plugins
2. launch gnome-do
3. enable microblogging plugin
4. enter your twitter credentials in the microblogging configuration dialog
5. Summon Do with <Super>space
6. Type your message to post to twitter
7. hit tab and search for "post to twitter"
8. press enter to send message
9. See failed message
10. go to twitter.com and see that the message posted
Although the post is successful, it reports a failure due to the XML reply reporting a negative post id from 32bit integer overflow. This negative post id also affects incoming messages and prevents them from being shown, so users are not receiving any timeline updates.
All users are affected.