latest update breaks user CSS / Accessibility settings

[JVD]

After the update to firefox 41.0+build3-0ubuntu0.14.04.1 was applied
on my x86_64 14.04.3 LTS system, the firefox 'about:' internal URL dialogs
displayed in white text on a white background .
This now includes dialogs like the "Preferences" / "Menu" dialogs.
So effectively it renders the whole browser's menu system unusable
if you have selected the : about:preferences#content :
     Preferences -> Colors -> "Override the colors specified by my selections above"
to be "Always" and you specify a dark background color (eg #202020) and a light
text color (eg #ffffff ) then all the menus are in white text and white background.

The previous firefox version correctly applied my "Override Colors Always" setting to the
"about:*" internal dialogs .

How can I get this behaviour back ?

Under KDE / Qt, ALL other applications correctly display in white text on black background .

[JVD (jason-vas-dias)]

Fixed with update of : 42.0+build2-0ubuntu0.14.04 - my about:preferences page finally displays in non-invisible about:preferences#content settings.