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+The rebuilding command
+
+     ikiwiki --setup mysite.setup --rebuild
+
+issues an error
+
+    multimarkdown is enabled, but Text::MultiMarkdown is not installed
+
+I then tried to install it on macOS using
+
+    brew install multimarkdown
+
+and then
+
+   sudo pkgin -y install multimarkdown
+
+and then rebuilding, but I still get the same error.
+
+Why and how do I fix it?