I couldn't find exact steps what I need to do in order to build and print my page locally as it would in https://devmanual.gentoo.org. So contributing a huge page is guesswork how it's going to end up in live. https://devmanual.gentoo.org/appendices/contributing/index.html https://devmanual.gentoo.org/appendices/contributing/index.html
The steps should be listed there: https://devmanual.gentoo.org/appendices/contributing/index.html#where-to-find-the-sources "Where to find the sources Currently, sources are hosted on git.gentoo.org. For current Gentoo developers, access is at git+ssh://git@git.gentoo.org/proj/devmanual.git. Non-developers can clone the repository by typing git clone git://anongit.gentoo.org/proj/devmanual.git. The sources are also hosted on GitHub for those who prefer to submit patches using pull requests. To build the devmanual, simply run make in the top directory of the repository. You need xsltproc (from dev-libs/libxslt) for the XML to HTML conversion, xmllint (from dev-libs/libxml2) for validation, and rsvg-convert (from gnome-base/librsvg) for the SVG to PNG conversion used in some of the figures throughout the document. To check if the document's XML is valid, run make validate in the top-level directory, which will validate all XML files using xmllint." Not enough?
Well, this is a bit embarrassing. I'd add a subtopic, Where to find the sources -> How to build the sources to make it more visible. Since, as proven, it can be missed while eyeballing through the document with only one thing in mind! Yeah this is on me.
