User Agent: Mozilla/5.0 (Windows NT 6.1; rv:19.0) Gecko/20100101 Firefox/19.0 Build ID: 20130215130331 Steps to reproduce: Opended a PDF document. Seems to be all PDF off the web that aren't scanned images affected. System has high contrast setting enabled. Background text would be black and foreground green even if it was not set. Actual results: Tried to render with green text overstamped on black text on white background, resulting in completely unreadable text. Expected results: Either apply user-selected colors or don't. Never mix and match.
Reproduces identically on Linux x64. Resetting platform to all.
It seems for me that every pdf that has a text layer has a very similar problem that the text is displayed twice (i.e. the hiddel layer is rendered like a drop shadow). E.g. http://people.mozilla.org/~jdaggett/css3fontspresentation.pdf displays nearly unreadable while https://www.mozilla.org/foundation/donate_form.pdf is just fine in black on white high contrast (Win8).