Access Steam features such as the user details, overlay, achievements, DLC, rich presence, and more.
The File System manual entry does say Windows WebView2 is an exception and can write files directly without prompting - see the section "Accessing known folders". The new Linux CEF export option is also an exception (but is currently in beta - the manual will be updated when it's stable), and in future macOS WKWebView will be supported too.
Sure, I will study more about the FileSystem, Thanks