In some cases, when you increase the size of your movie to full screen, the screen goes completely black. The problem is caused by Flash Player configuration. Most cases are easily solved by following these instructions:
1. Using your mouse, right-click on the black screen.
2. Select the “Configuration” option in the window that appears.
3. Deactivate the hardware acceleration.
Now you should be able to correctly watch your movies and TV series in full screen.