diff --git a/source/blender/blenkernel/BKE_blender_version.h b/source/blender/blenkernel/BKE_blender_version.h
index b3df809b4db..e4e6999425b 100644
--- a/source/blender/blenkernel/BKE_blender_version.h
+++ b/source/blender/blenkernel/BKE_blender_version.h
@@ -27,7 +27,7 @@
 
 /* Blender file format version. */
 #define BLENDER_FILE_VERSION BLENDER_VERSION
-#define BLENDER_FILE_SUBVERSION 96
+#define BLENDER_FILE_SUBVERSION 97
 
 /* Minimum Blender version that supports reading file written with the current
  * version. Older Blender versions will test this and cancel loading the file, showing a warning to
diff --git a/source/blender/blenloader/intern/versioning_500.cc b/source/blender/blenloader/intern/versioning_500.cc
index 8c6e1fdea38..336b63c2386 100644
--- a/source/blender/blenloader/intern/versioning_500.cc
+++ b/source/blender/blenloader/intern/versioning_500.cc
@@ -3694,6 +3694,24 @@ void blo_do_versions_500(FileData *fd, Library * /*lib*/, Main *bmain)
     }
   }
 
+  if (!MAIN_VERSION_FILE_ATLEAST(bmain, 500, 97)) {
+    /* Enable new "Optional Label" setting for all menu sockets. This was implicit before. */
+    FOREACH_NODETREE_BEGIN (bmain, tree, id) {
+      tree->tree_interface.foreach_item([&](bNodeTreeInterfaceItem &item) {
+        if (item.item_type != NODE_INTERFACE_SOCKET) {
+          return true;
+        }
+        auto &socket = reinterpret_cast<bNodeTreeInterfaceSocket &>(item);
+        if (!STREQ(socket.socket_type, "NodeSocketMenu")) {
+          return true;
+        }
+        socket.flag |= NODE_INTERFACE_SOCKET_OPTIONAL_LABEL;
+        return true;
+      });
+    }
+    FOREACH_NODETREE_END;
+  }
+
   /**
    * Always bump subversion in BKE_blender_version.h when adding versioning
    * code here, and wrap it inside a MAIN_VERSION_FILE_ATLEAST check.