With the top bar redesign (currently mod-only, broader rollout planned for the next couple of weeks) in Chrome the header seems not to be tall enough to contain its content anymore. In this image, you can see the blue translucent background under "QUESTIONS" overhanging the background pattern on the bottom, and under the "PHYSICS" logo, part of that image also overhangs the background.
I've tested this on a few browsers and found that it occurs with Chrome 60.0.3112.113 on OS X and Chromium 59.0.3071.104 on Linux, but not with Firefox 52.3.0 on Linux, Vivaldi 1.11.917.43 on Linux, or Safari 10.1.2 (12603.3.8) on OS X. So, seemingly Chrome-specific.
Can this be checked and fixed?