That selector actually matches up with a bit of Javascript just above it:
$('p.code').each(function (i, c) {
var code = $(c).find('tt.codetext').text().replace(/\u00a0/g,' ').
+replace(/\s+$/,'');
var dl = $(c).find('span.embed-code-dl');
var pre = $(
'<pre class="blockcode"><code>'
+ $('<div/>').text(code).html()
+ '</code></pre>'
);
var footer = $('<div style="text-align:right"><small></small></div
+>');
if (dl.html()) footer.find('small').append(dl.html());
$(c).after(footer);
$(c).replaceWith(pre);
});
The intention of that is to rewrite PerlMonks' code-block markup into a much simpler <pre class="blockcode"><code>...</code></pre>, which the syntax highlighter can then deal with.
However PerlMonks' code-block markup does vary depending on your display settings for code listings. My settings are:
Code Wrapping Off [ ]
Code Wrap Length [ ]
Auto Code Wrapping [ Yes ]
Code Prefix [ ]
Large Code Font [ ]
Don't show embedded d/l links [ ]
Show download link on code N lines long or more: [ 4 ]
If you let me know your settings I can try to make sure pm2.js works better with them.