YouTube full-screen video display is completely black


Problem: The YouTube video’s window becomes completely black or black/white after switching to full-screen mode.

Resolution:
 
1) Before switching to full-screen mode, right-click on the YouTube video window. After right-clicking you should see a menu like the following:

Selecting Adobe Flash Settings

2) Select Settings…
3) The Adobe Flash Player Settings dialog should appear and will look like the following:

Adobe Flash Settings Menu

4) As shown above, while on the Display tab of the Adobe Flash Player dialog, uncheck the “Enable hardware acceleration” checkbox and then save the change by pressing the “Close” button. This should resolve the issue with black YouTube video full-screen playback.