Great, you've hidden the message with javascript, but now it's still in view-source and in search results for bots. It's also still visible if someone is using

Great, you've hidden the message with javascript, but now it's still in view-source and in search results for bots. It's also still visible if someone is using noscript (actually, I have no idea if Facebook works with noscript, probably not). The solution you are suggestion doesn't solve the problem and injects more corner cases.