diff --git a/apps/edr-freight-web/backoffice/vite.config.ts b/apps/edr-freight-web/backoffice/vite.config.ts
index f5a3563a8..b6ec390a6 100644
--- a/apps/edr-freight-web/backoffice/vite.config.ts
+++ b/apps/edr-freight-web/backoffice/vite.config.ts
@@ -23,6 +23,7 @@ function userManagementSpaFallback() {
         rewrite(req);
         next();
       });
+      
     },
     configurePreviewServer(s: PreviewServer) {
       s.middlewares.use((req: IncomingMessage, _r: ServerResponse, next: () => void) => {
diff --git a/apps/edr-freight-web/portal/vite.config.ts b/apps/edr-freight-web/portal/vite.config.ts
index 3d8023494..99e2a41d5 100644
--- a/apps/edr-freight-web/portal/vite.config.ts
+++ b/apps/edr-freight-web/portal/vite.config.ts
@@ -7,6 +7,12 @@ import tailwindcss from "@tailwindcss/vite";
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
+// Pin Mantine to this app's copy. pnpm can install a second @mantine/core under
+// @edr/ui-common (linked to react@18) while the portal uses react@19 — dedupe
+// alone does not merge those into one module in production builds.
+const mantineCore = path.resolve(__dirname, "node_modules/@mantine/core");
+const mantineHooks = path.resolve(__dirname, "node_modules/@mantine/hooks");
+
 export default defineConfig({
   plugins: [react(), tailwindcss()],
   resolve: {
@@ -14,13 +20,14 @@ export default defineConfig({
       "@": path.resolve(__dirname, "./src"),
       // Resolve from TS source so Vite gets ESM named exports (dist is CommonJS).
       "@edr/types": path.resolve(__dirname, "../../../packages/types/src/index.ts"),
+      "@mantine/core": mantineCore,
+      "@mantine/hooks": mantineHooks,
     },
-    // Force a single copy of these singletons so MantineProvider context is
-    // shared between the portal app and @edr/ui-common (which ships its
-    // own node_modules copy). Without this, two separate @mantine/core
-    // instances are bundled and the context lookup fails at runtime.
     dedupe: ["react", "react-dom", "@mantine/core", "@mantine/hooks"],
   },
+  optimizeDeps: {
+    include: ["@mantine/core", "@mantine/hooks", "@edr/ui-common"],
+  },
   server: {
     port: 5173,
     host: "0.0.0.0",