Comment 0 for bug 1580168

When I hover the mouse button on top of the Firefox tabs, the tab descriptions are
unreadable, black text on black background.

This also happens on some other web sites which pop up a description box, e.g. on portal.azure.com when hovering over your username in the top right corner in the browser.

This probably started happening when Firefox was first compiled against gtk3.
My gtk3 theme is oxygen-gtk.

1) The Ubuntu release is 14.04.4
2) The version of Firefox is 46.0+build5-0ubuntu0.14.04.2
3) I expect to be able to read the tab descriptions
4) The tab descriptions are black text on black background