Free and open society means others doing things that I don't agree with. Including private CEO donations or leaving service because of politics. By definition, it is attribute of democracy.
There's a huge difference between enforcing reasonable immigration laws and what some right-wing parties are proposing. I don't know enough about this specific party, but you'll find similar ones in other countries. And remigration is in the end about deporting even legal and well integrated immigrants.
Freedom doesn't mean just what you think is acceptable. If a society feels like they let too many people into the country they have the freedom to undo it.
To make things clear my definition of a free society is one where the society itself governs how it is run. The opposite of this is when another country, organization, or person is dictating how it is run overriding how the society wants to do things.
>Do you consider [giving] governance of [the] majority to [the] minority as a part of free society?
I do not consider that as a requirement free society. While representational democracies give governance to a small amount of people compared to the overall populace theoretical you could have a society where everyone was on equal footing and all contributed to decisions being made.
I'm supporting your position elsewhere: mentioning to avoid being dismissed as right-wing/ethno-nationalist.
However, support for migration is not a left or right issue. Accepting refugees might be (and I fully support that), but non-refugee immigration (the vast majority of it) is not an unalloyed good.
Immigration has a number of negative effects, on housing, employment and wages, inequalities, social cohesion, political direction.
Being a radical leftist and against immigration is not contradictory.