Finding points for decorateWidget


Hi! How can I find the places where I can point my decorateWidget? I mean, I have the code api.decorateWidget('header-icons:before' etc. (for example), but how can I find other places such as header-icons:before where I can use the decorateWidget?

(I’m trying to find out how I could make another hamburger-menu, and I’m looking for the point to use.)