### 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
switch (vcs_actions_menu->get_item_id(p_idx)) {
		case RUN_VCS_METADATA: {
			VersionControlEditorPlugin::get_singleton()->popup_vcs_metadata_dialog();
		} break;
		case RUN_VCS_SETTINGS: {
			VersionControlEditorPlugin::get_singleton()->popup_vcs_set_up_dialog(gui_base);
		} break;
	}
}
void EditorNode::_update_title() {
	const String appname = GLOBAL_GET("application/config/name");
	String title = (appname.is_empty() ? TTR("Unnamed Project") : appname);
	const String edited = editor_data.get_edited_scene_root() ? editor_data.get_edited_scene_root()->get_scene_file_path() : String();
	if (!edited.is_empty()) {
		
		title = vformat("%s - %s", edited.get_file(), title);
	}
	if (unsaved_cache) {
		
		title = vformat("(*) %s", title);
	}
	DisplayServer::get_singleton()->window_set_title(title + String(" - ") + VERSION_NAME);
	if (project_title) {
		project_title->set_text(title);
	}
}
void EditorNode::shortcut_input(const Ref<InputEvent> &p_event) {