diff --git a/src/pages/Viewer.tsx b/src/pages/Viewer.tsx
index 92ab215..2638e61 100644
--- a/src/pages/Viewer.tsx
+++ b/src/pages/Viewer.tsx
@@ -3,6 +3,7 @@ import { supabase } from "@/integrations/supabase/client";
 import { ArrowLeft, Glasses, Box, Ruler, FileText, Upload, Loader2, Users, Menu, Target } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { useModelStore } from "@/stores/useModelStore";
+import { xrStore } from "@/stores/useXRStore";
 import { ModelViewerCanvas } from "@/components/three/ModelViewer";
 import { ViewerControls } from "@/components/ViewerControls";
 import { InspectionChecklist } from "@/components/InspectionChecklist";
@@ -274,12 +275,16 @@ const Viewer = () => {
     }, 15000);
 
     try {
-      const { xrStore } = await import('@/stores/useXRStore');
       // Marca que está entrando no AR antes de navegar — bloqueia auto-return prematuro
       (window as unknown as { __setXrEntering?: (v: boolean) => void }).__setXrEntering?.(true);
-      await xrStore.enterAR();
+      
+      // Chamada síncrona de enterAR para preservar o User Gesture exigido pelo WebXR
+      const enterPromise = xrStore.enterAR();
+      
       clearTimeout(timeoutId);
       navigate("/xr");
+      
+      await enterPromise;
     } catch (e) {
       clearTimeout(timeoutId);
       setEnteringXR(false);
diff --git a/src/stores/useModelStore.ts b/src/stores/useModelStore.ts
index c37a4cb..56ad8dd 100644
--- a/src/stores/useModelStore.ts
+++ b/src/stores/useModelStore.ts
@@ -812,3 +812,12 @@ export const useModelStore = create<ModelStore>((set, get) => ({
     set({ ifcMaterialColors: enabled });
   },
 }));
+
+// Autodetecção global de suporte a WebXR
+if (typeof navigator !== 'undefined' && navigator.xr) {
+  navigator.xr.isSessionSupported('immersive-ar')
+    .then((supported) => useModelStore.getState().setXrSupported(supported))
+    .catch(() => useModelStore.getState().setXrSupported(false));
+} else {
+  useModelStore.getState().setXrSupported(false);
+}