Repository: tauri-apps/tauri (language: rust)

Issue:
[bug] window.add_child dosen't work at tauri 2.0.5
### Describe the bug

window.add_child dosen't work at tauri 2.0.5

``` rust
 window
            .add_child(
                webview_builder,
                tauri::LogicalPosition::new(0, 86),
                PhysicalSize::new(size.width, size.height - 86),
            )
```
this code works well in tauri 2.0.1
![tauri 2.0.1](https://github.com/user-attachments/assets/67fab004-a05c-4c8b-b84c-b4a2699e1b5f)

but in tauri 2.0.5，it dosen't woked anymore.
![tauri 2.0.5](https://github.com/user-attachments/assets/8a76c59b-af78-4d62-9f00-ef51cb605615)



### Reproduction

_No response_

### Expected behavior

_No response_

### Full `tauri info` output

```text
Environment
  › OS: Windows 10.0.22631 X64
  › Webview2: 128.0.2739.79
  › MSVC:
      - Visual Studio Community 2022
  › Node.js: 18.20.2
  › npm: 10.5.0
  › pnpm: 9.4.0
  › yarn: 1.22.19
  › rustup: 1.27.1
  › rustc: 1.80.1
  › cargo: 1.80.1
  › Rust toolchain: stable-x86_64-pc-windows-msvc
```


### Stack trace

_No response_

### Additional context

_No response_


Discussion / hints:
tauri2.0.6 too,now i change the version to tauri2.0.2,it is work
![image](https://github.com/user-attachments/assets/070fee29-7db5-4972-9c0a-25e65769395d)


Fix patch:
diff --git a/.changes/child-windows-macos.md b/.changes/child-windows-macos.md
new file mode 100644
index 000000000000..4c9f52651702
--- /dev/null
+++ b/.changes/child-windows-macos.md
@@ -0,0 +1,7 @@
+---
+"tauri": "patch:bug"
+"tauri-runtime-wry": "patch:bug"
+---
+
+Fix regression in creating child webviews on macOS and Windows, covering the whole window.
+
diff --git a/crates/tauri-runtime-wry/src/lib.rs b/crates/tauri-runtime-wry/src/lib.rs
index bde9d3ccd7fd..12629db18420 100644
--- a/crates/tauri-runtime-wry/src/lib.rs
+++ b/crates/tauri-runtime-wry/src/lib.rs
@@ -4364,7 +4364,7 @@ fn create_webview<T: UserEvent>(
       target_os = "ios",
       target_os = "android"
     ))]
-    WebviewKind::WindowChild => webview_builder.build(&window),
+    WebviewKind::WindowChild => webview_builder.build_as_child(&window),
     WebviewKind::WindowContent => {
       #[cfg(any(
         target_os = "windows",


Test patch: