User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:15.0) Gecko/20100101 Firefox/15.0.1 Build ID: 20120905151427 Steps to reproduce: Switch into high contrast mode on windows. Find a site that has many small sprites, like an AJAX control; pandora and facebok are good ones. Actual results: The controls become impossible to navigate because the sprites have been reduced to plain black or deleted. The links and buttons that they attach to still work, but the site becomes impossible to navigate because every thing is invisible. Expected results: Nothing should ever be set to pure black or deleted from the page. A check should be performed when converting the image to high contrast and an error should be thrown if it is deleted or all black. Either the origional image should then be used or a different scheme for generating high contrast should be used. Process could even be rinse repeat.

To a better understanding of the problem, can you please provide some concrete facebook examples? Pandora is N/A outside of the U.S.

here is a facebook example. but I bet there are more sites that can be just as hard to navigate.

How Pandora looks in non high contrast... I circled the elements that are invisible in high contrast.

This picture illiterates the problem on some much more accessible sites.. Namely Google search and the start page in Firefox that displays recent page snap shots.

After some more research, This illistrates what is going on perfectly.. http://blog.adrianroselli.com/2012/08/css-background-images-high-contrast-mode.html in fact if you go to tools->options->content->colors and then uncheck the "allow pages to choose their own colors" you get the same behavior that I am describing with different background colors that are defined.

Do you still reproduce this in the latest nightly ?

(In reply to Paul Silaghi, QA [:pauly] from comment #6) > Do you still reproduce this in the latest nightly ? Latest nightly still has missing images.