### Godot version

v4.2.dev.custom_build [0c2144da9]

### System information

Debian Linux X11 Xfce

### Issue description

Prerequisite: Be in Single Window Mode in the Editor
The Filesystem Dock is unusable when it is floating, which is not expected.
It appears garbled in the top-left corner:
![image](https://github.com/godotengine/godot/assets/6299227/109f7922-97de-44c3-814a-ca7f970e0602)

The following errors are shown:
```
  editor/window_wrapper.cpp:220 - Condition "!is_window_available()" is true.
  editor/window_wrapper.cpp:202 - Condition "!get_window_enabled()" is true. Returning: Rect2i()
  editor/window_wrapper.cpp:207 - Condition "!get_window_enabled()" is true. Returning: -1
  editor/window_wrapper.cpp:207 - Condition "!get_window_enabled()" is true. Returning: -1
```

bisecting lead to #62378
possibly related to #44439

### Steps to reproduce

1. Start a project in the Editor
2. Switch to Single Window Mode in the Editor and reload (if necessary)
3. Make the Filesystem Dock floating

### Minimal reproduction project

Editor issue
DisplayServer::get_singleton()->clipboard_set(warning->get_text());
}
void EditorNode::_dock_floating_close_request(WindowWrapper *p_wrapper) {
	int dock_slot_num = p_wrapper->get_meta("dock_slot");
	int dock_slot_index = p_wrapper->get_meta("dock_index");
	
	Control *dock = p_wrapper->release_wrapped_control();
	dock_slot[dock_slot_num]->add_child(dock);
	dock_slot[dock_slot_num]->move_child(dock, MIN(dock_slot_index, dock_slot[dock_slot_num]->get_tab_count()));
	dock_slot[dock_slot_num]->set_current_tab(dock_slot_index);
	floating_docks.erase(p_wrapper);
	p_wrapper->queue_free();
	_update_dock_containers();
	_edit_current();
}
void EditorNode::_dock_make_selected_float() {
	Control *dock = dock_slot[dock_popup_selected_idx]->get_current_tab_control();
	_dock_make_float(dock, dock_popup_selected_idx);
	dock_select_popup->hide();
	_edit_current();
}
void EditorNode::_dock_make_float(Control *p_dock, int p_slot_index, bool p_show_window) {