auto-git:

[change] src/document/scene-document-validation.ts

src/document/scene-document-validation.ts

@@ -191,7 +191,8 @@ function validateWorldBackgroundSettings(
   document: SceneDocument | ProjectDocument,
   diagnostics: SceneDiagnostic[],
   path: string,
-  label: string
+  label: string,
+  options: { allowEmptyImageAssetId?: boolean } = {}
 ) {
   if (background.mode === "solid") {
     if (!isHexColorString(background.colorHex)) {
@@ -238,6 +239,7 @@ function validateWorldBackgroundSettings(
     typeof background.assetId !== "string" ||
     background.assetId.trim().length === 0
   ) {
+    if (!options.allowEmptyImageAssetId) {
       diagnostics.push(
         createDiagnostic(
           "error",
@@ -246,6 +248,7 @@ function validateWorldBackgroundSettings(
           `${path}.assetId`
         )
       );
+    }
   } else {
     const backgroundAsset = document.assets[background.assetId];