Here's a picture from the Badges page on Meta:
The text "Help Center > Badges" is black, but all the other pages are white:
The low contrast makes the text much harder to read. Since both "Help Center" and "Badges" are links, they should probably be red instead. Or at least not black.
I can reproduce on the latest builds of Chrome and Firefox on Windows 7, and I can see the CSS rule which causes this:
.subheader a {
color: #000;
}
so I suspect this affects most, if not all, browsers.
The same rule is also applied on the main site, where it makes more sense (the other tabs have dark blue subheadings). Nonetheless, it should be changed for Meta.
ETA: Here’s another page showing the same problem.