None I'm aware of. Firefox is a < 5minute install, and you should have it anyway if you're going to develop websites. Often different browsers render sites differently. Colorzilla installs in 30 seconds or so.

While you're at it, install the Web Developer plugin too, which let me see that the background color of those headers is:

.leftBoxHeading, .centerBoxHeading, .rightBoxHeading {
margin: 0em;
background-color: #a07c6e;
padding: 0.5em 0.2em;
}