Thanks for your replies. I see that it's also required in other countries.

So I'm a little curious that if a protest is related to complaints about the government, will it get accepted (at most cases)?

most of them will not be accepted or considered at all. in very rare case, protest will be accepted or encouraged, most of them have gov behind it.

Is not that the same in other countries? In Russia you also need to negotiate the protest at least 10 days before the event (and the government has lot of excuses to deny it).

In US, the First Amendment protects "right of the people peaceably to assemble", so the ability to restrict it via permits is somewhat limited. In general, a permit is only required if the protest is large enough to be significantly disruptive. Normally this means that so long as you can stay on the sidewalks without disrupting pedestrian traffic, you're good.

Sometimes, municipalities still try to block protests because of politics/people they don't like participating, under the guise of some more neutral explanation (usually noise or safety). But judges generally take a dim view on such shenanigans, and they rarely pass scrutiny in the courtroom, since the government is then expected to explain the exact grounds for denial, and prove that it is relevant and narrowly tailored.

Also in Germany, you have to announce it to the Police

I believe in the US as well if you're organizing a protest on public property you need a permit in some areas.