You said below you live in a country where holocaust denial is illegal. No matter whether it's morally supportable, that's censorship.
P.S. Before anyone misunderstands this statement: Being a supporter of free speech does not mean that you support any of the truly idiotic and wrong opinions that it allows people to express. The point was more generally that whenever a government says "it is illegal to express opinion X", that's censorship (unfortunately no matter how upsetting you may find X).
On the internet, except in a few places, everyone is free to start their own website and post whatever opinion they want, so the "censorship" argument is almost always complete junk. It's the equivalent of someone whining they didn't get let into some club by the bouncer - they're free to make that decision not to let you in, and you're still free to go party somewhere else.