diff --git a/playground/rmgi/demo/3p-form3-uischema.json b/playground/rmgi/demo/3p-form3-uischema.json
index 722f4d2f..f333f90f 100644
--- a/playground/rmgi/demo/3p-form3-uischema.json
+++ b/playground/rmgi/demo/3p-form3-uischema.json
@@ -1 +1,3 @@
-{"name":{"ui:options":{"readonly": true}}}
\ No newline at end of file
+{
+    "name":{"ui:options":{"readonly": true}},
+}
\ No newline at end of file