src/vs/workbench/contrib/notebook/browser/view/cellParts/cellToolbars.ts/BetweenCellToolbar/_initialize
class BetweenCellToolbar:	private _initialize(): ToolBar {
		if (this._betweenCellToolbar) {
			return this._betweenCellToolbar;
		}

		const betweenCellToolbar = this._register(new ToolBar(this._bottomCellToolbarContainer, this.contextMenuService, {
			actionViewItemProvider: action => {
				if (action instanceof MenuItemAction) {
					if (this._notebookEditor.notebookOptions.getLayoutConfiguration().insertToolbarAlignment === 'center') {
						return this.instantiationService.createInstance(CodiconActionViewItem, action, undefined);
					} else {
						return this.instantiationService.createInstance(MenuEntryActionViewItem, action, undefined);
					}
				}

				return undefined;
			}
		}));

		this._betweenCellToolbar = betweenCellToolbar;
		const menu = this._register(this.menuService.createMenu(this._notebookEditor.creationOptions.menuIds.cellInsertToolbar, this.contextKeyService));
		const updateActions = () => {
			const actions = getCellToolbarActions(menu);
			betweenCellToolbar.setActions(actions.primary, actions.secondary);
		};

		this._register(menu.onDidChange(() => updateActions()));
		this._register(this._notebookEditor.notebookOptions.onDidChangeOptions((e) => {
			if (e.insertToolbarAlignment) {
				updateActions();
			}
		}));

		updateActions();

		return betweenCellToolbar;
	}