diff --git a/system/blueprints/pages/modular.yaml b/system/blueprints/pages/modular.yaml
index e90f1d2ee..e744be727 100644
--- a/system/blueprints/pages/modular.yaml
+++ b/system/blueprints/pages/modular.yaml
@@ -44,3 +44,7 @@ form:
               type: ignore
             uploads:
               type: ignore
+
+            header.body_classes:
+                type: hidden
+                default: 'modular'