Content shouldn't exceed the profile sidebar

Fixes #5346. (The second half because the first half is a duplicate)

Before:
![](https://cloud.githubusercontent.com/assets/3798614/5256386/23744ba4-79c8-11e4-8ca9-8f469de0d152.png)

After:
![](https://cloud.githubusercontent.com/assets/3798614/5256389/2e8d53fa-79c8-11e4-827f-737ea58b7c1c.png)