jQuery Accordion, when expanded shows visual artifact in Google Chrome extension's popup window, only on a Mac

I've asked this question on the stackoverflow site but I couldn't get an answer. Please read my detailed account of the issue here . That link also has a screengrab of the issue that I made to illustrate what happens.

The question I have for the people on this forum -- does this look like an issue with the jQuery/Accordion or is it a Chrome bug?