How to stop unwanted full-screen exit since update of plug-in?

Since installing NPAPI 21.0.0.226 & PPAPI 21.0.0.213 on my MacBook Pro this weekend, when streaming tv episodes on Hulu (using Auto-Play), every time a new episode starts, the browser window drops out of full screen mode.  I contacted Hulu support & they had me tinker with the Flash Player admin settings, but I'm still having the same problem.  Any suggestions for how to fix this?  Auto play isn't much use when I have to manually reset the window to full-screen every new episode.  I haven't tested whether this is also happening now on other streaming sites like Netflix yet.