You're using Chrome, It's not working?
I've spent weeks trying to figure out Google Chrome for 420chan. The solution was all too simple and all of my browsing through the script's actual text was a waste of my time. So this is for my 420chan brothers and bitches..
On the little toolbar that pops up after you have installed the extension, restarted, and visited 420chan.org, you should UNCHECK "hide threads." Voila, problem solved, and if not, hit "reload page" on the toolbar.
I can't believe I wasted so much of my life trying to figure this out. I'm not usually the generous type but I feel bad for any poor soul who had to do what I did. So again, UNCHECK "hide threads." You now win.
If you want to be thankful, or pretend to be, just imagine me floating in a California ocean; whoever it is, that I am in your mind. For when you form that mental image, a little piece of me is projected there and my freezing Illinois mind might just be quieted. Slayer.