upgraded, but TDE video issue

Thanks to Slávek, I've just had the least-painful system upgrade in the (heavens! can it be?) 20 years I've run Linux exclusively. It wasn't totally trouble-free, but it was less awful than I usually encounter. But now I'm encountering a problem that is annoying: menus in Firefox and some other applications are reversed, white text on black background. Any quick and easy fix? Am running 14.04 on Ubuntu 14.04 (and preparing to revel in the new features everyone else has had for three years . . .). Thanks again. -- dep The shortest distance between you and playing great acoustic guitar: the great new instructional DVDs from Marjorie Thompson, available at www.MarjorieThompson.com