I did a quick search and was surprised that I didn't find it already reported. (Though this issue also involved tooltips in that area).
Using Firefox 39.0, I tried to see what Impact meant, and the top of the tooltip was cut off, as shown in the image below. I was also able to reproduce the issue in Internet Explorer 11.0.
This only seems to happen with the fancy dark tooltip that appears when viewing my own profile (as opposed to the default tooltip that appears when viewing other profiles).
As @NormalHuman pointed out, this also happens on WebApps. That bug mentions the following browsers:
- Safari (Mac OS)
- Google Chrome (Windows 8.1)