In this context it means when a group of people labelled as Hipsters (people who search unique ways of living) move to a certain area that they believe to be "cool". If you watch a Netflix comedy series called 'Unbreakable' you'll see one character fighting off hipsters so they won't make her area a cool trend and thus, changing her favorite aspects of the place. I'm not a native English speaker but I hope I could help you with what I know.