If freedom of speech is absolute, how come it's not applied for private spaces and for the Internet?

No freedom is absolute.

That’s what it is. You have no right to use other people’s stuff. If people let you use their stuff, they can tell you how you can use it, and they can tell you to stop using it any time they want.

You have freedom of speech. If I loan you my computer, I can tell you not to use it for certain things, because it’s mine, you have no right to use it, and if I give you permission to use it I can tell you what you can and can’t do with it.

What is the correct way to say "you're welcome" in French? Is it "de rien" or something else, and if so, what is it exactly (including accent marks)?

HIPAA violations

Perjury

Fraud

Accidental discovery at New York planetarium unlocks secret into universe’s inner workings - PBS

Terroristic threats

If you’re wondering why free speech doesn’t apply to the internet, it’s because you have no right to use other people’s stuff for free.

Revenge porn

Why do almost all the girls on Quora look beautiful?

False advertising

Child pornography

Conspiracy

I’ve Figured Out a Method for Keeping My Son’s Favorite Toy Clean. It Might Lead to Some Trust Issues. - Slate Magazine

Insider trading

Trade secrets

And much, much more.

In Italy, how do people greet each other when they meet for the first time (e.g., on the street)? What's a good response to that greeting if you're not from Italy or don't speak Italian fluently yet?

You have freedom to travel. If I loan you my car, I can tell you not to take it out of town, because it’s mine, you have no right to use it, and if I give you permission to use it I can tell you what you can and can’t do with it.

Revealing classified information

Freedom of speech does not apply to:

What is a good tool for product analytics besides Google Analytics?

Insurrection

Threats of violence