Fullscreen Flash video only shows 1/4 of video When I maximize some Flash (version 15.0.0.xxx) videos to fullscreen, only the top left quarter of the screen is showing video, the rest is completely black.

I've tried this on OSX 10.9 and 10.10, 2014 Macbook Pro, 3 browsers (Safari, Chrome, and Firefox) with no plugins, no additional screen, and hardware acceleration set to enabled and disabled.

Here's a workaround I've found: right click on the 1/4-screen video and look for the Stretching is &lt;type&gt; item in the options list. Click on that and the video will fill the screen. Keep repeating to get back to the 'Stretching is none' setting.

What can I do to debug this?
I've found it. After looking a little further, I was able to find something I missed some time ago.


  
  In the URL bar enter chrome://plugins/
  Locate the Flash plug-in, you should see multiple versions listed
  Click Disable for the plug-in with the location /opt/google/chrome/PepperFlash/libpepflashplayer.so
  You should still have one enabled in another location, like /usr/lib/adobe-flashplugin/libflashplayer.so
  Restart Chrome (quit and open again)
  


Source: https://code.google.com/p/chromium/issues/detail?id=135353#c25

This fixed it for me!