Further tune focus stealing prevention in

`MinimalWindowManager::advise_new_window`

src/miral/minimal_window_manager.cpp

@@ -298,22 +298,23 @@ auto miral::MinimalWindowManager::confirm_inherited_move(WindowInfo const& windo
 
 void miral::MinimalWindowManager::advise_new_window(miral::WindowInfo const& window_info)
 {
-    self->application_selector.advise_new_window(window_info, self->focus_stealing == FocusStealing::allow);
-
-    auto const should_be_pushed_back = [](auto const& window_info)
-    {
-        return window_info.type() == mir_window_type_normal || window_info.type() == mir_window_type_utility;
-    };
-
     // If focus stealing prevention is on, swap the old focused window (now in
     // the back) with the new window in the front.
+    //
     // If it's a legitimate window, it'll be focused and raised via
     // xdg-activation.
-    if ((self->focus_stealing == FocusStealing::prevent) && tools.active_window() &&
-        should_be_pushed_back(window_info))
-    {
+    //
+    // This is limited to a couple of window types, as well as windows in the
+    // "application" layer that don't have a parent.
+    auto in_background =
+        (self->focus_stealing == FocusStealing::prevent) && tools.active_window() &&
+        (window_info.type() == mir_window_type_normal || window_info.type() == mir_window_type_freestyle) &&
+        window_info.depth_layer() == mir_depth_layer_application && !window_info.parent();
+
+    self->application_selector.advise_new_window(window_info, in_background);
+
+    if (in_background)
         tools.swap_tree_order(tools.active_window(), window_info.window());
-    }
 }
 
 void miral::MinimalWindowManager::advise_focus_gained(WindowInfo const& window_info)