Up till recently the usermanual has been only available for those who got the source and the necessary tools to generate and even than it would generate a HUGE pdf file due to the amount of high resolution of screenshots. I revisited the build system with the goals of shrink-en the size of the final PDF and to produce an html output that could be integrated in our website.
This is a companion discussion topic for the original entry at https://www.darktable.org/2011/03/darktable-user-manual-revisited/