diff --git a/make-pages/Info.hs b/make-pages/Info.hs
index 99ead1f..a587899 100644
--- a/make-pages/Info.hs
+++ b/make-pages/Info.hs
@@ -16,7 +16,7 @@ import Records
 
 import Control.Applicative
 import Control.Exception
-import Data.Foldable (find)
+import Data.Foldable (find, foldl')
 import Data.Hashable (Hashable)
 import Data.HashSet (HashSet)
 import qualified Data.HashSet as HashSet
@@ -149,7 +149,15 @@ instance Semigroup Desc where
   (TextDesc t1) <> (TextDesc t2) = TextDesc $ t1 <> t2
   (LongDesc m1) <> (TextDesc t2) = LongDesc $ m1 <> [DescField defDescKey t2]
   (TextDesc t1) <> (LongDesc m2) = LongDesc $ [DescField defDescKey t1] <> m2
-  (LongDesc m1) <> (LongDesc m2) = LongDesc $ m1 <> m2
+  (LongDesc m1) <> (LongDesc m2) = LongDesc $ mergeDesc m1 m2
+
+mergeDesc :: [DescField] -> [DescField] -> [DescField]
+mergeDesc = foldl' $ flip add where
+  add d2 = map \d1 ->
+    if #name d1 == #name d2 then
+      d1 {text = #text d1 <> #text d2}
+    else
+      d1
 
 instance Monoid Desc where
   mempty = NoDesc
diff --git a/make-pages/make-pages.cabal b/make-pages/make-pages.cabal
index 3e9121f..9ff3431 100644
--- a/make-pages/make-pages.cabal
+++ b/make-pages/make-pages.cabal
@@ -35,6 +35,7 @@ executable make-pages
     DerivingStrategies,
     DerivingVia,
     DuplicateRecordFields,
+    FlexibleContexts,
     FlexibleInstances,
     GeneralizedNewtypeDeriving,
     LambdaCase,