### Godot version

v4.0.beta.custom_build [eaf306e0b]

### System information

Windows 10

### Issue description

Selecting a `Window` node in the Editor's SceneTree results in the message
```
editor/editor_data.cpp:1058 - Parameter "p_node" is null.
```
and the Inspector shows empty content instead of the Window's properties.

I would expect, that clicking on a node in the SceneTree lets me edit the properties of the node.

Bisecting shows that this behavior got introduced in #71770

### Steps to reproduce

1. Create a Window node
2. Click on the Window node in the Editor's SceneTree

### Minimal reproduction project

N/A
} else {
			type_icon = EditorNode::get_singleton()->get_class_icon(E, "NodeDisabled");
		}
		TreeItem *type_node = import_items_tree->create_item(root);
		type_node->set_meta("_can_be_imported", false);
		type_node->set_collapsed(true);
		type_node->set_icon(0, type_icon);
		type_node->set_text(0, type_name);
		type_node->set_cell_mode(IMPORT_ITEM, TreeItem::CELL_MODE_CHECK);
		type_node->set_checked(IMPORT_ITEM, false);
		type_node->set_editable(IMPORT_ITEM, true);
		type_node->set_cell_mode(IMPORT_ITEM_DATA, TreeItem::CELL_MODE_CHECK);
		type_node->set_checked(IMPORT_ITEM_DATA, false);
		type_node->set_editable(IMPORT_ITEM_DATA, true);
		bool is_matching_filter = (filter_text.is_empty() || type_name.findn(filter_text) > -1);
		bool has_filtered_items = false;
		for (int i = 0; i < Theme::DATA_TYPE_MAX; i++) {
			Theme::DataType dt = (Theme::DataType)i;
			names.clear();
			filtered_names.clear();
			base_theme->get_theme_item_list(dt, E, &names);
			bool data_type_has_filtered_items = false;
			for (const StringName &F : names) {
				String item_name = (String)F;
				bool is_item_matching_filter = (item_name.findn(filter_text) > -1);
				if (!filter_text.is_empty() && !is_matching_filter && !is_item_matching_filter) {
					continue;
				}
				
				if (!filter_text.is_empty() && is_item_matching_filter) {