Surely a sign of TEOTWAWKI:

Bill Gates Inadvertently Shows Off Ubuntu on His Facebook Page

Screencapped, in case it goes down the memory hole:

(Yes, the likely explanation is that he pulled a stock photo from somewhere, but you’d think he, of all people, would’ve spent a few minutes extra to find a stock photo with a Windows desktop.  Hell, he could’ve called someone in Microsoft’s PR department to either find an image or have one made on short order.)