src/vs/workbench/contrib/notebook/browser/viewParts/notebookKernelView.ts/NotebooKernelActionViewItem/_update
class NotebooKernelActionViewItem:	protected _update(): void {
		const notebook = this._editor.textModel;

		if (!notebook) {
			this._resetAction();
			return;
		}

		const kernelPickerType = this._configurationService.getValue<'all' | 'mru'>('notebook.kernelPicker.type');
		if (kernelPickerType === 'mru') {
			KernelPickerMRUStrategy.updateKernelStatusAction(notebook, this._action, this._notebookKernelService);
		} else {
			KernelPickerFlatStrategy.updateKernelStatusAction(notebook, this._action, this._notebookKernelService, this._editor.scopedContextKeyService);
		}

		this.updateClass();
	}