### Godot version

master

### System information

Godot v4.2.beta (0ea75d77c) - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2070 (NVIDIA; 31.0.15.3598) - Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (12 Threads)

### Issue description

When any of the Import, Filesystem, Node, or History docks are floating, changing an editor feature crashes the engine.
Changing any setting or selecting a different profile triggers it.

This is because `EditorNode::_feature_profile_changed` assumes the docks are in a `TabContainer`, and if they are floating they aren't in one.


### Steps to reproduce

Make any of these docks floating: Import, Filesystem, Node, or History
Open Editor Features (Editor -> Manage Editor Features...)
Make a profile (if you have none) or change a setting on the existing profile

### Minimal reproduction project

n/a
if (owner) {
					Ref<SceneState> ss_inst = owner->get_scene_instance_state();
					if (ss_inst.is_valid()) {
						ss_inst->update_instance_resource(p_instance_path, current_packed_scene);
					}
					owner->set_editable_instance(instantiated_node, is_editable);
				}
				
				for (AdditiveNodeEntry additive_node_entry : addition_list) {
					Node *parent_node = instantiated_node->get_node_or_null(additive_node_entry.parent);
					if (!parent_node) {
						parent_node = current_edited_scene;
					}
					parent_node->add_child(additive_node_entry.node);
					parent_node->move_child(additive_node_entry.node, additive_node_entry.index);
					
					if (additive_node_entry.owner == original_node) {
						additive_node_entry.owner = instantiated_node;
					}
					additive_node_entry.node->set_owner(additive_node_entry.owner);
					
					{
						Node2D *node_2d = Object::cast_to<Node2D>(additive_node_entry.node);
						if (node_2d) {
							node_2d->set_transform(additive_node_entry.transform_2d);
						}
						Node3D *node_3d = Object::cast_to<Node3D>(additive_node_entry.node);
						if (node_3d) {
							node_3d->set_transform(additive_node_entry.transform_3d);
						}