WinForms with CEFSharp lose background and begin transparent - winforms

Question

I use WinForms with CEFSharp 41.0.1 and have next problem: the background of the application (google.com is opened) lose background and begin transparent on the Windows 7 from the beginning till the end and provide same behavior when switching system users on the Windows 8 until focusing the app.
Furthermore, for Windows 8 the application sometimes can not take focus in after it, you are trying to focus in input in google but go through the application to the background app. This is very big trouble for our app.
I cannot show Windows 7 case now, so I show the behavior for Windows 8 with changing system users after Ctrl + Alt + Delete -> Switch User
Screenshots for Windows 8 (before switching users):
Screenshots for Windows 8 (after switching system users):
For that case is impossible to take a screenshot because whenever you focus in application, it re-renders and looks correctly.
I use next code for creating browser object and adding to the form:
_browser = new ChromiumWebBrowser("google.com")
{
Dock = DockStyle.Fill,
MenuHandler = new CustomMenuHandler(),
BrowserSettings = new BrowserSettings()
{
ApplicationCacheDisabled = false,
FileAccessFromFileUrlsAllowed = true,
JavascriptDisabled = false,
LocalStorageDisabled = false,
WebSecurityDisabled = true,
JavaScriptOpenWindowsDisabled = false,
JavascriptDomPasteDisabled = false,
}
};
RegisterWrappers();
Controls.Add(_browser);
and next code for the initialization:
Cef.Initialize(new CefSettings()
{
CachePath = "cache"
});
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Context(new Form1()));
Appreciate any ideas.

Answer 1

The solution is to delete TransparencyKey property from the WinForms. In our project it was set to White and white background content in browser becomes transparent in Windows 7 but for Windows 8 it is not work correctly so it was difficult to detect problem.