Uneven spacing in menu comment in HTML output

[Gavin Smith]

If you look at a page like
https://www.gnu.org/software/texinfo/manual/texinfo/html_node/index.html#toc-Command-and-Variable-Index-1
and scroll down to a "comment" in the menu, for example the "Using
Texinfo Mode" line, you'll see that there's more space below the line
than above, which looks bad. Looking at the source it looks like:

<tr><th colspan="3" align="left" valign="top"><pre class="menu-comment">
Using Texinfo Mode

</pre></th></tr>

, which has three newlines between the opening <pre> tag and the
closing </pre> tag. I suspect, however, that the first one,
immediately after <pre>, is being ignored.

Any clues what the correct way to stop the first newline from being
ignored is? I've looked for documentation online about the HTML <pre>
tag, but nothing I've seen so far addresses this point.