diff --git a/debian/lighttpd/89-dump1090-fa.conf b/debian/lighttpd/89-dump1090-fa.conf
index 09b5a27..5ac6041 100644
--- a/debian/lighttpd/89-dump1090-fa.conf
+++ b/debian/lighttpd/89-dump1090-fa.conf
@@ -3,7 +3,22 @@
 # data and are periodically written by the dump1090 daemon.
 
 # Enable alias module
-server.modules += ( "mod_alias" )
+#
+## This module is normally already enabled in lighttpd, so you should not
+## need to uncommment this line.
+## There are some cases (e.g. when installing this on a Raspberry Pi
+## that runs PiHole) in which the module has been removed from the
+## default configuration, and the dump1090-fa web interface no longer
+## loads properly.
+## If this is what you are experiencing, or if you see messages in your
+## error log like:
+## (server.c.1493) WARNING: unknown config-key: alias.url (ignored)
+## then uncommenting this line and then restarting lighttpd could fix
+## the issue.
+## This is not enabled by default as standard lighttpd will not start if
+## modules are loaded multiple times.
+#
+# server.modules += ( "mod_alias" )
 
 alias.url += (
   "/dump1090-fa/data/" => "/run/dump1090-fa/",