You can also use uMatrix or NoScript to disable all JS/XHR (or even CSS and images) from third-party domains by default; and whitelist those you need.
How can I block cookies with uMatrix for sub domains like *.domain.com for any site?
PS: I assume that just temporary solution. Because nextsstep is just hosting some js from "analytics" on main domain and/or solutions like cloudflare for e-commerce / google news / etc.
And for filtering that bs we need deep filtering and api inside JS VM