WTF?? Anyone have an idea what the system that produces this is called?

You can read or listen to a recent (and very explicit / potentially offensive) description of how it works and why it came to be: https://mollyrocket.com/jacs/jacs_0004_0010.html

Its generated from C code. You can avoid the shittyness of web "technologies" by manually positioning everything.

Now I understand why Pocket chokes on it... too bad.