src/vs/workbench/contrib/notebook/browser/contrib/cellStatusBar/executionStatusBarItemController.ts/TimerCellStatusBarItem/_formatDuration
class TimerCellStatusBarItem:	private _formatDuration(duration: number) {
		const seconds = Math.floor(duration / 1000);
		const tenths = String(duration - seconds * 1000).charAt(0);

		return `${seconds}.${tenths}s`;
	}