Change tooltip background color in VS2015

Question

In VS2015 I have the Color Theme Editor extension installed and I\'m using the Dark with Light Editor theme.

The hover tooltips are mostly unreadable as the tooltip

Answer 1

I am also using Color Theme Editor Extension with the custom theme, based on "Dark with light editor". Actually, the background color of the tooltip for me was
Environment -> CommandBarMenuBackgroundGradientBegin.
(see Brandon's answer on how to change it)
IDE Screenshot