I could probably open it up and look at each frame individually, but that'd be like watching that Magics Greatest Secrets Revealed with that dude off the X Files.
If you look closely, you'll see that it appears while he's being slapped. I understand where you're having difficulty, though; the first few times I watched the video I was convinced the beard appeared 30 seconds after his being slapped.
I could probably open it up and look at each frame individually, but that'd be like watching that Magics Greatest Secrets Revealed with that dude off the X Files.
Use Esc (if you have a non-******ed browser) to freeze the gif. Your reflexes should be quick from all the ninja-refreshing you do.