code: function onTimeKeydown(event) {
  		const { keyCode, shiftKey } = event;
  
  		// 37: LEFT, 38: UP, 39: RIGHT, 40: DOWN
  		if (37 <= keyCode && 40 >= keyCode) {
  			event.preventDefault();
  
  			const isLTR = /^(btt|ltr)$/.test(timeDir);
  			const offset = 37 === keyCode || 39 === keyCode ? keyCode - 38 : keyCode - 39;
  
  			media.currentTime = Math.max(0, Math.min(duration, currentTime + offset * (isLTR ? 1 : -1) * (shiftKey ? 10 : 1)));
  
  			onTimeChange();
  		}
  	}
docs: keydown from play control or current time control