This page, its companion page and the two linked stylesheets serve as an example for MozillaFirebird bug #224014 that I reported.
Normally, when you specify two stylesheets in your HTML document, one with media=screen and one with media=print, Firebird will automatically pick the correct stylesheet when you're viewing the page in the browser, or sending it to the printer. However, this behaviour is broken when a title attribute is specified for both stylesheets.
1) View this page in the browser, make a mental note of the purple background and the presence of the menu block.
2) Now select Print Preview or just print the page.
That the page is now black-and-white, and that the menu block has been hidden.
The page is rendered without styling.
In the html header, the stylesheets are included like this:
<link rel="stylesheet" type="text/css" title="Normal stylesheet" href="screen.css" media="screen"/>
<link rel="stylesheet" type="text/css" title="Printer stylesheet" href="print.css" media="print"/>
The thing to notice is the presence of the title attribute in combination with the media attribute.