diff --git a/web/maplibre-demo.js b/web/maplibre-demo.js
index da84e45..6b33834 100644
--- a/web/maplibre-demo.js
+++ b/web/maplibre-demo.js
@@ -140,7 +140,7 @@ function is3DAsset(asset) {
   if (!asset) return false;
   const kind = String(asset.kind || "").toLowerCase();
   const ext = normalizeExt(asset.ext) || extFromLink(asset.link);
-  return kind === "3d" && (ext === "glb" || ext === "gltf");
+  return kind === "3d" && ext === "glb";
 }
 
 async function renderSharedAssetFromQuery() {
@@ -344,6 +344,12 @@ async function addObjectMeshFromAsset(featureId, lng, lat, asset, cycleID) {
   }
 
   if (!is3DAsset(asset) || !asset.link) {
+    const ext = normalizeExt(asset.ext) || extFromLink(asset.link);
+    if (String(asset.kind || "").toLowerCase() === "3d" && ext === "gltf") {
+      console.warn(
+        `Feature ${featureId} uses .gltf. Map rendering supports self-contained .glb via /download; using fallback shape.`
+      );
+    }
     addFallbackMesh(featureId, lng, lat, Boolean(asset.isPublic), asset.kind || "3d");
     return false;
   }
@@ -542,6 +548,9 @@ async function createFeatureAndUpload() {
   if (!ext) {
     throw new Error("File extension is required.");
   }
+  if (ext === "gltf") {
+    setStatus("Note: .gltf may fail on map if it references external files. Prefer .glb for reliable 3D rendering.");
+  }
 
   await ensureCollection();
   const featureName = assetNameEl.value.trim() || file.name;