--strip-comments ignored for alternative markdown formats

[dubiousjim]

Explain the problem.

These are as documented:

$ printf -- '<!-- text -->' | pandoc -fmarkdown -thtml
<!-- text -->
$ printf -- '<!-- text -->' | pandoc -fmarkdown -tnative
[ RawBlock (Format "html") "<!-- text -->" ]
$ printf -- '<!-- text -->' | pandoc -fmarkdown -thtml --strip-comments

$ printf -- '<!-- text -->' | pandoc -fmarkdown -tnative --strip-comments
[]

These are surprising:

$ printf -- '<!-- text -->' | pandoc -fcommonmark -thtml --strip-comments
<!-- text -->
$ printf -- '<!-- text -->' | pandoc -fcommonmark -tnative --strip-comments
[ RawBlock (Format "html") "<!-- text -->\n" ]

Same results for -fgfm and -fcommonmark_x.

Minimally, I'd encourage this to be more explicitly declared in the documentation, which now just says:

--strip-comments
Strip out HTML comments in the Markdown or Textile source, rather than passing them on to Markdown, Textile or HTML output as raw HTM...

Sometimes "Markdown" in the docs is used to cover all of these formats, not just Pandoc-flavored Markdown.

Ideally, though, I'd prefer (at least) the -fcommonmark_x reader to honor the --strip-comments flag.

Pandoc version?
pandoc 2.19 on OS X, custom cabal build with --flags=lua53