src/vs/workbench/contrib/notebook/browser/viewModel/baseCellViewModel.ts/BaseCellViewModel/getSelectionsStartPosition
class BaseCellViewModel:	getSelectionsStartPosition(): IPosition[] | undefined {
		if (this._textEditor) {
			const selections = this._textEditor.getSelections();
			return selections?.map(s => s.getStartPosition());
		} else {
			const selections = this._editorViewStates?.cursorState;
			return selections?.map(s => s.selectionStart);
		}
	}