How can I create a new post in blogdown with a .Rmd extension?

I'm trying to create an R Markdown file using the function blogdown::new_post("my new post"), but it always creates a straight markdown file with a .md extension.

In the RStudio addin there is an option to change the format to either .Rmd or .Rmarkdown (https://bookdown.org/yihui/blogdown/rstudio-ide.html#fig:new-post)

Is there any way to specify R Markdown format with the command line function?

To create R Markdown files with blogdown on the command line, I've found 2 different options:

1. With the function blogdown::new_post(), use the parameter ext e.g. blogdown::new_post("my new post", ext=".Rmd")
2. Set .Rmd or .Rmarkdown as the default extension by adding an option in the .Rprofile file e.g. option(blogdown.ext = ".Rmd") (Reload the R environment after updating.)

For further information on global options see: https://bookdown.org/yihui/blogdown/global-options.html

I didn't find any specific documentation on the function parameters, but entering the function name without the brackets in the terminal e.g. blogdown::new_post shows the function definition including different possible parameters:

function (title, kind = "", open = interactive(), author = getOption("blogdown.author"),
    categories = NULL, tags = NULL, date = Sys.Date(), time = getOption("blogdown.time",
        FALSE), file = NULL, slug = NULL, title_case = getOption("blogdown.title_case"),
    subdir = getOption("blogdown.subdir", "post"), ext = getOption("blogdown.ext",
        ".md"))
{