Investigating why it is that you can’t block Facebook CEO Mark Zuckerberg on Facebook, Mashable discovered a safeguard makes it so once someone has been blocked enough, future blockage is prevented.

Here is what Facebook told Mashable:

This error isn’t specific to any one account. It’s generated when a person has been blocked a certain large number of times. In very rare instances, a viral campaign will develop instructing lots of people to all wrongly block the same person. The purpose of this system is to protect the experience for people targeted by these campaigns. We’re constantly working to improve our systems and are taking a closer look at this one.

So in case you were ever worried about Zuckerberg spamming you with YouTube forwards, be very afraid, because nothing can stop him.

Why You Can’t Block Mark Zuckerberg on Facebook [Mashable]

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