Provide the theme summaries for the following conversation: 

Frederick: Hmm... What do you think about Brexit?
Harry: I think it was not necessary 
Henry: Yep
Henry: you knew that the guy which came up with the idea of Brexit resigned from his position?
Frederick: seriously? I didn't know that
Harry: yea, me too
Henry: and what will happen with all the people who are living there for not so long and they are foreigners
Frederick: It is a good question
Harry: I have heard that people who stayed there for like 5 years or so will not have problems with staying in GB
Henry: i've also heard that
Henry: and what will happen with those who had been living there for a shorter period of time?
Frederick: I think that they must on Teresa's mercy
Harry: hah, I think there will be no mercy for them
Henry: I also think the same way, they will be deported and their journey in GB will end

Summary: 
Harry thinks Brexit was not necessary. The guy who came up with this idea resigned from his position. People who have stayed in GB for more than 5 years will be able to stay. The fate of those with less than 5 years is uncertain. Harry and Henry think they will be deported.