$ mkdocs build
INFO - Cleaning site directory
INFO - Building documentation to directory: /tmp/mkdocs-with-pdf/samples/mkdocs-material/site
WARNING - Missing article: [Home]()
INFO - Number headings up to level 3.
INFO - Generate a table of contents up to heading level 2.
INFO - Generate a cover page with "default_cover.html.j2".
INFO - Generate a back cover page with "default_back_cover.html.j2".
INFO - Converting <img> alignment(workaround).
INFO - Converting <iframe> to poster image(if available).
INFO - Converting for two-column layout(heading level 3).
INFO - Rendering on `Headless Chrome`(execute JS).
INFO - Rendering for PDF.
INFO - Output a PDF to "/tmp/mkdocs-with-pdf/samples/mkdocs-material/site/../document.pdf".
ERROR - No anchor #.: for internal URI reference
INFO - Converting 38 articles to PDF took 272.3s
INFO - Documentation built in 275.89 seconds