src/vs/workbench/contrib/notebook/browser/notebookEditor.ts/NotebookEditor/createEditor
class NotebookEditor:	protected createEditor(parent: HTMLElement): void {
		this._rootElement = DOM.append(parent, DOM.$('.notebook-editor'));

		// this._widget.createEditor();
		this._register(this.onDidFocus(() => this._widget.value?.updateEditorFocus()));
		this._register(this.onDidBlur(() => this._widget.value?.updateEditorFocus()));
	}