diff --git a/src/document/scene-document-validation.ts b/src/document/scene-document-validation.ts
index 8a2ed7cc..a5d34276 100644
--- a/src/document/scene-document-validation.ts
+++ b/src/document/scene-document-validation.ts
@@ -978,7 +978,8 @@ function validateWorldTimePhaseProfile(
     `${path}.background`,
     `${label}-background`,
     {
-      allowEmptyImageAssetId: true
+      allowEmptyImageAssetId: true,
+      allowShader: false
     }
   );