Sometimes my Thunderbird icon show a leaning notification as showned below, i.e., not straight as it used to be. It's like the unread mail notification was bending to the right. Every time this happens, the only solution is to restart the graphical interface.
Screenshot from 2013-07-01 12:38:15.png
All comments and suggestions are welcome!
PS: I'm using Ubuntu 13.04 (x86) on a Thinkdpad X60s
Graphical Controller Intel Corporation Mobile 945GM/GMS/GME
Intel® Core™ Duo CPU L2400 @ 1.66GHz × 2