I follow Kottke.org which has lots of videos. Recently, videos were no longer shown in the preview pane, instead showing a beveled empty box where the video should be (comparing to the actual blog page, the box is the correct size for the video displayed)
At first, I thought this was due to some browser extension I had loaded but I opened an incognito window and it is the same thing. It’s been happening for about two weeks now.
I’m using Chrome Version 30.0.1599.101 m on Windows 7 Pro, no extensions.