### 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
SceneTreeDock::get_singleton()->instantiate(p_path);
}
void EditorNode::request_instantiate_scenes(const Vector<String> &p_files) {
	SceneTreeDock::get_singleton()->instantiate_scenes(p_files);
}
void EditorNode::_inherit_request(String p_file) {
	current_menu_option = FILE_NEW_INHERITED_SCENE;
	_dialog_action(p_file);
}
void EditorNode::_instantiate_request(const Vector<String> &p_files) {
	request_instantiate_scenes(p_files);
}
void EditorNode::_close_messages() {
	old_split_ofs = center_split->get_split_offset();
	center_split->set_split_offset(0);
}
void EditorNode::_show_messages() {