I revised R.nvim documentation and noted three features that were not implemented as they were in Nvim-R:

1. When sending a marked block to R, the line of the second mark should not be included. It was defined this way in Nvim-R to allow users to mark various lines in an R script and send one block after the other. If both, the first and the second marks had their lines included, each marked line would be sent twice. I still would like to find an efficient way of replacing vim.fn.line("$") for which lua_ls warns that the result might nil.

2. Opening an HTML was not being like a PDF, although the options are the same (0: don't open; 1: open, but don't focus; 2: open and focus). I fixed the implementation and added a note to the documentation explaining that in many cases R.nvim will not be able to do what is expected. I moved the function that focuses the window from pdf/init.lua to utils.lua because now it's also used to focus a browser window.

3. When going to a previous/next chunk of code (Rmd, Quarto, or Rnoweb), the variable v:count must be considered. For example, 3\gn means "jump to the third chunk below". This happened automatically in VimScript, but I had to code it manually in Lua.

I believe this pull request is ready to be merged, but, of course, it would be better if someone could review it.

Thank you! I will merge it.