Some fix

- Avatar not display on Firefox #V3
![](https://dl.dropboxusercontent.com/u/2347680/Screenshot/Capture%20d%27%C3%A9cran%20-%2027052013%20-%2010%3A57%3A29.png)

- Tatam's preview display bug
![](https://dl.dropboxusercontent.com/u/2347680/Screenshot/Capture%20d%27%C3%A9cran%20-%2022052013%20-%2011%3A22%3A42%20%28copie%29.png)