Well it's relative...
If law enforcement is turning a blind eye and allowing murder, arson, and rape out in the open, unchecked, or if they're in on it themselves:Go nuts.
If it's something like petty theft or general spraypainting, the occasional fight and being a douche, or the law enforcement actually does their job:No.
Also, vigilantism is very complicated. Because, you have effectively made yourself a criminal. If the cops have really turned a blind eye, I doubt they'll start caring until you cross some line though.
Things will start get confusing when you can't tell the difference between an armed thug and the vigilante though. Both behave the same way towards each other, and a criminal could always lie about what side they are on.
TBH, the best scenario is encourage self-defense. Don't chase them down and become the monster you hate, because that makes things complicated. Just kick their ass when they come up.
They pull a knife on you? Feel free to stab them and get out of there. But don't start home invasions and personal vendettas.