You can specify -webkit-app-region: drag in CSS to tell CefSharp which regions are draggable (like the OS's standard titlebar), and apps can also use -webkit-app-region: no-drag to exclude the non-draggable area from the draggable region. Note that only rectangular shapes are currently supported.
To make the whole window draggable, you can add -webkit-app-region: drag as body's style:
<body style="-webkit-app-region: drag">
</body>And note that if you have made the whole window draggable, you must also mark buttons as non-draggable, otherwise it would be impossible for users to click on them:
button {
-webkit-app-region: no-drag;
}If you're only setting a custom titlebar as draggable, you also need to make all buttons in titlebar non-draggable.