To this list I would add "Web Browser Engineering" [0] which is a textbook / browser engine that is currently being written by Dr. Pavel Panchekha at the University of Utah. The code for the book and browser is available on GitHub [1] and a more current bleeding edge draft is also published [2].
The book guides the reader in implementing a graphical web browser, starting with HTTP and HTML then moving on to the layout, the box model, CSS, browser chrome, forms, and scripts.
[0] https://browser.engineering