See this topic on the CEF C++ forum for more details:

http://www.magpcss.org/ceforum/viewtopic.php?f=6&t=10641

Do the following changes in the CEF C++ sources:

1. In `chromium/src/cef/libcef/browser/browser_host_impl_gtk.cc`:

At the end of the CefBrowserHostImpl::PlatformCreateWindow() function,

before the return statement add the following code:

gtk_widget_show_all(GTK_WIDGET(window_info_.widget));

In the same function replace this code:

gtk_container_add(GTK_CONTAINER(window_info_.parent_widget),

window_info_.widget);

With the following code:

if (GTK_IS_BOX(window_info_.parent_widget)) {

gtk_box_pack_start(GTK_BOX(window_info_.parent_widget),

window_info_.widget, TRUE, TRUE, 0);

} else {

// Parent view shouldn't contain any children, but in wxWidgets library

// there will be GtkPizza widget for Panel or any other control.

GList *children, *iter;

children = gtk_container_get_children(GTK_CONTAINER(

window_info_.parent_widget));

GtkWidget* child = NULL;

GtkWidget* vbox = gtk_vbox_new(FALSE, 0);

for (iter = children; iter != NULL; iter = g_list_next(iter)) {

child = GTK_WIDGET(iter->data);

// We will have to keep a reference to that child that we remove,

// otherwise we will get lots of warnings like "invalid unclassed

// pointer in cast to `GtkPizza'". First we increase a reference,

// we need to do this for a moment before we add this child to the

// vbox, then we will decrease that reference.

g_object_ref(G_OBJECT(child));

gtk_container_remove(GTK_CONTAINER(window_info_.parent_widget), child);

}

g_list_free(children);

gtk_box_pack_start(GTK_BOX(vbox), window_info_.widget, TRUE, TRUE, 0);

if (child != NULL) {

// This child is packed to the box only so that its reference lives,

// as it might be referenced from other code thus resulting in errors.

gtk_box_pack_end(GTK_BOX(vbox), child, FALSE, FALSE, 0);

gtk_widget_hide(GTK_WIDGET(child));

g_object_unref(G_OBJECT(child));

}

gtk_widget_show(GTK_WIDGET(vbox));

if (GTK_IS_SCROLLED_WINDOW(window_info_.parent_widget))

gtk_scrolled_window_add_with_viewport(

GTK_SCROLLED_WINDOW(window_info_.parent_widget), vbox);

else

gtk_container_add(GTK_CONTAINER(window_info_.parent_widget), vbox);

}