Following https://bookdown.org/yihui/bookdown/get-started.html I have downloaded https://github.com/rstudio/bookdown-demo/archive/main.zip
I open the project in RStudio, open index.Rmd and select "Knit to gitbook" The resulting HTML has the expected TOC and index.html page, but selecting any chapter on the TOC brings to an empty page. This is in contradiction with "By default, bookdown merges all Rmd files by the order of filenames"