I'm going to leave mean comments on a girls youtube video
Why would you want to leave mean comments on a girl's youtube video?
She's a little bitch and deserves it as far as I can tell
Youtube channels can be really silly and immature. Being mean about it won't solve anything, it will just provoke drama.
No, I have to tell her how dumb she is.
Being rude to her isn't going to make you or anyone else feel good. If you don't like her then you should just stop watching her videos and forget about her.