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Signal messenger blocked in Russia, says Roskomnadzor
(www.reuters.com)
This is a most excellent place for technology news and articles.
How would you? You’d have to block every instance.
They could start by blocking the biggest instances, then slowly chasing after the smaller ones.
There's not an infinite amount of instances, even if new ones are made, they'll get all of them eventually. So this is basically a cat and mouse game.