diff --git a/IkiWiki/Plugin/mdwn.pm b/IkiWiki/Plugin/mdwn.pm
index 66116ae01..eefa29a97 100644
--- a/IkiWiki/Plugin/mdwn.pm
+++ b/IkiWiki/Plugin/mdwn.pm
@@ -89,6 +89,55 @@ sub htmlize (@) {
 		    (! exists $config{nodiscount} || ! $config{nodiscount})) {
 			eval q{use Text::Markdown::Discount};
 			if (! $@) {
+				my $markdown = \&Text::Markdown::Discount::markdown;
+				my $always_flags = 0;
+
+				# Disable Pandoc-style % Title, % Author, % Date
+				# Use the meta plugin instead
+				$always_flags |= Text::Markdown::Discount::MKD_NOHEADER();
+
+				# Disable Unicodification of quote marks, em dashes...
+				# Use the typography plugin instead
+				$always_flags |= Text::Markdown::Discount::MKD_NOPANTS();
+
+				# Workaround for discount's eliding of <style> blocks.
+				# https://rt.cpan.org/Ticket/Display.html?id=74016
+				if (Text::Markdown::Discount->can('MKD_NOSTYLE')) {
+					$always_flags |= Text::Markdown::Discount::MKD_NOSTYLE();
+				}
+				elsif ($markdown->('<style>x</style>', 0) !~ '<style>' &&
+					$markdown->('<style>x</style>', 0x00400000) =~ m{<style>x</style>}) {
+					$always_flags |= 0x00400000;
+				}
+
+				# Enable fenced code blocks in libmarkdown >= 2.2.0
+				# https://bugs.debian.org/888055
+				if (Text::Markdown::Discount->can('MKD_FENCEDCODE')) {
+					$always_flags |= Text::Markdown::Discount::MKD_FENCEDCODE();
+				}
+				elsif ($markdown->("~~~\nx\n~~~", 0) !~ m{<pre\b} &&
+					$markdown->("~~~\nx\n~~~", 0x02000000) =~ m{<pre\b}) {
+					$always_flags |= 0x02000000;
+				}
+
+				# PHP Markdown Extra-style term\n: definition -> <dl>
+				if (Text::Markdown::Discount->can('MKD_DLEXTRA')) {
+					$always_flags |= Text::Markdown::Discount::MKD_DLEXTRA();
+				}
+				elsif ($markdown->("term\n: def\n", 0) !~ m{<dl>} &&
+					$markdown->("term\n: def\n", 0x01000000) =~ m{<dl>}) {
+					$always_flags |= 0x01000000;
+				}
+
+				# Allow dashes and underscores in tag names
+				if (Text::Markdown::Discount->can('MKD_GITHUBTAGS')) {
+					$always_flags |= Text::Markdown::Discount::MKD_GITHUBTAGS();
+				}
+				elsif ($markdown->('<foo_bar>', 0) !~ m{<foo_bar} &&
+					$markdown->('<foo_bar>', 0x08000000) =~ m{<foo_bar\b}) {
+					$always_flags |= 0x08000000;
+				}
+
 				$markdown_sub=sub {
 					my $t=shift;
 
@@ -96,15 +145,7 @@ sub htmlize (@) {
 					# https://rt.cpan.org/Ticket/Display.html?id=73657
 					return "" if $t=~/^\s*$/;
 
-					my $flags=0;
-
-					# Disable Pandoc-style % Title, % Author, % Date
-					# Use the meta plugin instead
-					$flags |= Text::Markdown::Discount::MKD_NOHEADER();
-
-					# Disable Unicodification of quote marks, em dashes...
-					# Use the typography plugin instead
-					$flags |= Text::Markdown::Discount::MKD_NOPANTS();
+					my $flags=$always_flags;
 
 					if ($config{mdwn_footnotes}) {
 						$flags |= Text::Markdown::Discount::MKD_EXTRA_FOOTNOTE();
@@ -114,42 +155,6 @@ sub htmlize (@) {
 						$flags |= Text::Markdown::Discount::MKD_NOALPHALIST();
 					}
 
-					# Workaround for discount's eliding
-					# of <style> blocks.
-					# https://rt.cpan.org/Ticket/Display.html?id=74016
-					if (Text::Markdown::Discount->can("MKD_NOSTYLE")) {
-						$flags |= Text::Markdown::Discount::MKD_NOSTYLE();
-					}
-					else {
-						# This is correct for the libmarkdown.so.2 ABI
-						$flags |= 0x00400000;
-					}
-
-					# Enable fenced code blocks in libmarkdown >= 2.2.0
-					# https://bugs.debian.org/888055
-					if (Text::Markdown::Discount->can("MKD_FENCEDCODE")) {
-						$flags |= Text::Markdown::Discount::MKD_FENCEDCODE();
-					}
-					else {
-						$flags |= 0x02000000;
-					}
-
-					# PHP Markdown Extra-style term\n: definition -> <dl>
-					if (Text::Markdown::Discount->can("MKD_DLEXTRA")) {
-						$flags |= Text::Markdown::Discount::MKD_DLEXTRA();
-					}
-					else {
-						$flags |= 0x01000000;
-					}
-
-					# Allow dashes and underscores in tag names
-					if (Text::Markdown::Discount->can("MKD_GITHUBTAGS")) {
-						$flags |= Text::Markdown::Discount::MKD_GITHUBTAGS();
-					}
-					else {
-						$flags |= 0x08000000;
-					}
-
 					return Text::Markdown::Discount::markdown($t, $flags);
 				}
 			}
diff --git a/doc/bugs/discount_stopped_rendering_markdown_links.mdwn b/doc/bugs/discount_stopped_rendering_markdown_links.mdwn
index 1d70c926e..cfe544b02 100644
--- a/doc/bugs/discount_stopped_rendering_markdown_links.mdwn
+++ b/doc/bugs/discount_stopped_rendering_markdown_links.mdwn
@@ -34,3 +34,8 @@ Some guesses:
 > Orthogonally, pkgsrc should probably use an up-to-date version of Discount, and
 > [we already know that Text::Markdown::Discount needs updating](https://rt.cpan.org/Public/Bug/Display.html?id=124188).
 > --[[smcv]]
+
+>> This should be [[fixed|done]] in current git. The mdwn module now
+>> detects what your version of Discount supports by trying several
+>> short HTML fragments that render differently under the different
+>> flags. --[[smcv]]
diff --git a/t/mdwn.t b/t/mdwn.t
index 93b8bd8e9..ca3180139 100755
--- a/t/mdwn.t
+++ b/t/mdwn.t
@@ -8,6 +8,7 @@ BEGIN { use_ok("IkiWiki"); }
 
 %config=IkiWiki::defaultconfig();
 $config{srcdir}=$config{destdir}="/dev/null";
+$config{disable_plugins}=["htmlscrubber"];
 IkiWiki::loadplugins();
 IkiWiki::checkconfig();
 
@@ -41,4 +42,25 @@ like(IkiWiki::htmlize("foo", "foo", "mdwn",
 	"This works[^1]\n\n[^1]: Sometimes it doesn't.\n"),
 	qr{<p>This works<sup\W}, "footnotes can be enabled");
 
+SKIP: {
+	skip 'set $IKIWIKI_TEST_ASSUME_MODERN_DISCOUNT if you have Discount 2.2.0+', 4
+		unless $ENV{IKIWIKI_TEST_ASSUME_MODERN_DISCOUNT};
+	like(IkiWiki::htmlize("foo", "foo", "mdwn",
+			"Definition list\n: A useful HTML structure\n"),
+		qr{<dl>.*<dt>Definition list</dt>\s*<dd>A useful HTML structure</dd>}s,
+		"definition lists are enabled by default");
+	like(IkiWiki::htmlize("foo", "foo", "mdwn",
+			"```\n#!/bin/sh\n```\n"),
+		qr{<pre>\s*<code>\s*[#]!/bin/sh\s*</code>\s*</pre>}s,
+		"code blocks are enabled by default");
+	like(IkiWiki::htmlize("foo", "foo", "mdwn",
+			"<foo_bar>"),
+		qr{<foo_bar>},
+		"GitHub tag name extensions are enabled by default");
+	like(IkiWiki::htmlize("foo", "foo", "mdwn",
+			"<style>foo</style>"),
+		qr{<style>foo</style>},
+		"Styles are not stripped by default");
+}
+
 done_testing();