don't set isActive for a category on indices

src/Build.hs

@@ -153,18 +153,13 @@ putIsActive page@Page{..} = page { pageDoc = addMeta "isActive" isActiveMeta pag
         Nothing -> MetaMap Map.empty
         Just category -> MetaMap $ Map.singleton category $ MetaBool True
 
-    -- isActive.category.foo is true for pages that have the category foo, and for pages that are an index for foo
+    -- isActive.category.foo is true for pages that have the category foo
     isActiveMetaCategory :: MetaValue
-    isActiveMetaCategory = MetaMap $ insertIndex $ fromList $ map helper pageCategories where
+    isActiveMetaCategory = MetaMap $ fromList $ map helper pageCategories where
 
         helper :: Text -> (Text, MetaValue)
         helper category = (category, MetaMap $ Map.singleton category $ MetaBool True)
 
-        insertIndex :: Map Text MetaValue -> Map Text MetaValue
-        insertIndex meta = case indexFor page of
-            Nothing -> meta
-            Just category -> Map.insert category (MetaBool True) meta
-
     -- isActive.page.foo is true if the current page has the slug foo
     isActiveMetaPage :: MetaValue
     isActiveMetaPage = let Pandoc meta _ = pageDoc in case lookupMetaPlain "slug" meta of