dom: expose browser window constructor identity

crates/obscura-js/js/bootstrap.js

@@ -3715,6 +3715,17 @@ Object.defineProperty(globalThis.Window, Symbol.hasInstance, {
   value(obj) { return obj === globalThis || (obj && obj.window === obj); },
   configurable: true,
 });
+// A browser global is a Window object, not merely an object accepted by
+// `Window[Symbol.hasInstance]`. Framework environment gates (including Ember's)
+// also require the direct identity `self.constructor === Window`; leaving the
+// inherited Object constructor makes them enter their server-rendering path
+// and hand string selectors to DOM render operations.
+Object.defineProperty(globalThis, 'constructor', {
+  value: globalThis.Window,
+  writable: true,
+  configurable: true,
+  enumerable: false,
+});
 
 
 // Remove the static _iframeRegistry and replace with dynamic getters.

crates/obscura-js/src/runtime.rs

@@ -1809,6 +1809,23 @@ mod tests {
         assert_eq!(title, serde_json::json!("Test Page"));
     }
 
+    #[test]
+    fn global_window_has_browser_constructor_identity() {
+        let mut rt = setup_runtime("<html><body></body></html>");
+        let result = rt
+            .evaluate(
+                "return [window === self, self.constructor === Window,\
+                         window instanceof Window, self.document === document,\
+                         self.location === location, self.history === history,\
+                         self.navigator === navigator];",
+            )
+            .unwrap();
+        assert_eq!(
+            result,
+            serde_json::json!([true, true, true, true, true, true, true])
+        );
+    }
+
     #[test]
     fn explicit_viewport_is_distinct_from_fingerprinted_screen() {
         let dom = parse_html("<html><body></body></html>");