Author here.

That article, along with a number of other resources, are listed here:

https://browser.engineering/bibliography.html

In my view, a critical part of really learning how something as complicated as a browser works is by trying to build it yourself. That's why our book is oriented around building a browser as you go.

This also looks great. Might you or anyone else know where to find the accompanying video? I get "Sorry This video does not exist." for the embedded video link.