Just print to PDF. Somewhat annoying but whatever. For me the correct scale seems to be "page width" or 75%.
With the right tools, it can likely be used to compile the book into a proper PDF, rather than using print workarounds.
Seems, reading the book on the browser is the only option, that is how I did it since many weeks.
Fortunately, as mentioned in my post at the root level, there's PDFs available in the usual archivist libraries.