### 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
}
		ObjectID editor_owner_id = editor_owner->get_instance_id();
		if (main_plugin && !skip_main_plugin) {
			
			Resource *current_res = Object::cast_to<Resource>(current_obj);
			if (main_plugin->get_name() == "Script" && current_res && !current_res->is_built_in() && (bool(EDITOR_GET("text_editor/external/use_external_editor")) || overrides_external_editor(current_obj))) {
				if (!changing_scene) {
					main_plugin->edit(current_obj);
				}
			}
			else if (main_plugin != editor_plugin_screen && (!ScriptEditor::get_singleton() || !ScriptEditor::get_singleton()->is_visible_in_tree() || ScriptEditor::get_singleton()->can_take_away_focus())) {
				
				editor_plugin_screen->edit(nullptr);
				active_plugins[editor_owner_id].erase(editor_plugin_screen);
				
				editor_select(plugin_index);
				main_plugin->edit(current_obj);
			} else {
				editor_plugin_screen->edit(current_obj);
			}
			is_main_screen_editing = true;
		} else if (!main_plugin && editor_plugin_screen && is_main_screen_editing) {
			editor_plugin_screen->edit(nullptr);
			is_main_screen_editing = false;
		}
		edit_item(current_obj, editor_owner);
	}
	InspectorDock::get_singleton()->update(current_obj);
}
void EditorNode::_android_build_source_selected(const String &p_file) {