Steam forum members dug through newly released files from the recently launched open beta and dug up a handful of Mac OS X-specific graphics, like the open, maximize and minimize jewel icons that are used in the operating system's windows.
While those icons could be chalked up to Steam's change to a WebKit-based rendering engine for the client—Valve has moved away from Microsoft's Internet Explorer for Steam's new UI—there are a few other Mac-specific graphics buried within. That includes system dock graphics and a handful of OS X menu files.