[Problem/Bug]: Why is the title displayed here?

What happened?

When using WebView2, if I set a transparent background for both WebView2 and the webpage, an unknown status bar appears at the top of the window. It displays the current page’s title, and if no title is set, it shows the current URL. This bar does not appear when the application first starts, but it shows up after I click on the WebView2 page. When I resize the window, it disappears again.
It seems that this URL status bar is always present, but it is normally hidden by the background. When a transparent background is set, it becomes visible.

Importance

Important. My app's user experience is significantly compromised.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

No response

SDK Version

No response

Framework

Win32

Operating System

Windows 10

OS Version

19044.3086

Repro steps

1. download project：https://github.com/MicrosoftEdge/WebView2Samples/tree/main/GettingStartedGuides/Win32_GettingStarted
2. set a transparent background：

// line 124
Microsoft::WRL::ComPtr<ICoreWebView2Controller2> controller2;
HRESULT col2hr = webviewController->QueryInterface(IID_PPV_ARGS(&controller2));
if (SUCCEEDED(col2hr) && controller2) {
	COREWEBVIEW2_COLOR transparentColor = { 0, 0, 0, 0 };
	controller2->put_DefaultBackgroundColor(transparentColor);
}

3. navigate a transparent background url.
4. click webview2(html) page.

Repros in Edge Browser

No, issue does not reproduce in the corresponding Edge version

Regression

Don't know

Last working version (if regression)

No response

Start with the Win32_GettingStarted sample and inspect the transparent-background code at line 124, then follow the repro steps to compare the WebView2 window before and after clicking the page. Confirm whether the title or URL bar appears only with transparency and determine the expected behavior for the sample on Windows 10.