Nested HTML <ul> outputs an empty line after each markdown bullet

[step-]

pandoc 3.1.9, Linux - thank you for today's new release.

Below, the first <ul> list is good when converted to markdown but the second one has issues: to my surprise, an empty line is appended after each markdown list item.

If this isn't a bug as I think, what is the reason for appending an empty line after each bullet item of the second markdown list?

I would expect that a single html list produced a single markdown list instead of three. In turn, markdown viewers display an empty line after each bullet, which is a problem.

stdin (html):

<ul>
  <li>1</li>
  <li>2</li>
</ul>

<hr>

<ul>
  <li>1</li>
  <li>2</li>
    <ul>
      <li>a</li>
    </ul>
</ul>

stdout (markdown):

-   1
-   2

------------------------------------------------------------------------

-   1

-   2

-   -   a

native:

[ BulletList
    [ [ Plain [ Str "1" ] ] , [ Plain [ Str "2" ] ] ]
, HorizontalRule
, BulletList
    [ [ Plain [ Str "1" ] ]
    , [ Plain [ Str "2" ] ]
    , [ BulletList [ [ Plain [ Str "a" ] ] ] ]
    ]
]

[jgm]

Shouldn't the ul there be embedded in a li if you want a nested list?
See https://stackoverflow.com/questions/5899337/proper-way-to-make-html-nested-list

[jgm]

Anyway, the real question is why this is being treated as a "loose" list (with spaces between lines) rather than a "tight" one.

[jgm]

Turns out the command test for #8150 has almost the same test case.

[step-]

Shouldn't the ul there be embedded in a li if you want a nested list?

Good point but I didn't write the HTML from scratch. I copied/pasted it from SeaMonkey HTML composer, which is a GUI app. So yes, it is invalid HTML but it is also used in practice. SeaMonkey outputs an HTML 4.01 transitional doctype.

Thank you for the speedy fix! and for #8150; together they enable SeaMonkey composer output.

Anyway, the real question is why this is being treated as a "loose" list (with spaces between lines) rather than a "tight" one.

I don't know about "spaces between lines". Honestly all I can recall is the commonmark definition of a loose list, quote: "... The difference in HTML output is that paragraphs in a loose list are wrapped in <p> tags, while paragraphs in a tight list are not." and I can't say if the quoted sentence implies there should be spaces between lines.