diff --git a/usr.bin/less/lesspipe.sh b/usr.bin/less/lesspipe.sh
--- a/usr.bin/less/lesspipe.sh
+++ b/usr.bin/less/lesspipe.sh
@@ -25,4 +25,6 @@
 	*.zst)
 		exec zstd -d -q -c "$1"	2>/dev/null
 		;;
+	*)	exec cat "$1"		2>/dev/null
+		;;
 esac