diff --git a/src/missing-types.d.ts b/src/missing-types.d.ts
index 8d8366ae..9174f20e 100644
--- a/src/missing-types.d.ts
+++ b/src/missing-types.d.ts
@@ -39,3 +39,7 @@ declare var ga: {
   (...args: any[]): void;
   q: any[];
 };
+
+interface Navigator {
+	readonly standalone: boolean;
+}