Fix broken sponsored row in Firefox

From:
![1413275278](https://cloud.githubusercontent.com/assets/708296/4625949/1ea7fdd6-537c-11e4-99af-ce105eeeddec.png)

To:
![1413275289](https://cloud.githubusercontent.com/assets/708296/4625951/270dfe3a-537c-11e4-87ef-ffcd9490b0a0.png)