I am probably very unaware of a Chrome or Firefox extension that allows this: I wish I could Browse to... and set scripts to run before a page is navigated to.

I am probably very unaware of a Chrome or Firefox extension that allows this: I wish I could Browse to... and set scripts to run before a page is navigated to. I know you can do this from the Dev Tools console just by hooking into events, but i wish there were something more user-friendly so it'd be easy to pass around scripts to average users. Simply to unreference or wrap JS APIs that allow things like this. You'd still need to be impossibly aware of what new API Google is introducing in Chrome every week. I wish they defined subsets of JS, like how there's a C++ embedded standard and such. I know in JS land you go by feature detection not profile selection (like OpenGL?). We're just learning more ways to sandbox I suppose. PS: I want the ability to easily re-order the scripts that run before/after an event fires.