Presumably as an example of where it doesn't need to go? The graphical representations are incomprehensible at first glance. I'm sure you can learn to understand them, but at that point why not just learn how to read the textual representation? Especially when it doesn't even uphold its claim of being equivalent. The textual representation shows some kind of error handling, but I can find nothing in the graphical representation that indicates that there is error states.

Would be really nice if this browser would work on RISC OS https://www.riscosopen.org/content/