Bug with the shadows when using Renko chart types? (an image, source data and a source code included)

[ProgrammingLife]

Maybe I'm using this part of library incorrect? I've attached my source code, source data and the image as a output for that data. It looks like:

And my source code is:

let json = '[{"time":1551398400,"open":3814.26,"high":3857,"low":3813.01,"close":3823,"volume":23175,"mainPrice":3823},{"time":1551484800,"open":3822.17,"high":3841.31,"low":3772.25,"close":3819.93,"volume":19446,"mainPrice":3819.93},{"time":1551571200,"open":3819.97,"high":3835,"low":3781.32,"close":3807.75,"volume":16718,"mainPrice":3807.75},{"time":1551657600,"open":3807.32,"high":3830,"low":3670.69,"close":3715.3,"volume":34743,"mainPrice":3715.3},{"time":1551744000,"open":3716.1,"high":3877.1,"low":3703.55,"close":3857.73,"volume":32963,"mainPrice":3857.73},{"time":1551830400,"open":3857.58,"high":3907,"low":3813.09,"close":3861.84,"volume":24775,"mainPrice":3861.84},{"time":1551916800,"open":3861.84,"high":3905.4,"low":3840.4,"close":3873.64,"volume":26455,"mainPrice":3873.64},{"time":1552003200,"open":3873.63,"high":3932,"low":3800,"close":3864.89,"volume":34730,"mainPrice":3864.89},{"time":1552089600,"open":3864.88,"high":3971.75,"low":3854.75,"close":3943.04,"volume":30980,"mainPrice":3943.04},{"time":1552176000,"open":3943.43,"high":3943.43,"low":3881.69,"close":3916.82,"volume":23188,"mainPrice":3916.82},{"time":1552262400,"open":3915.99,"high":3936.98,"low":3830,"close":3871.61,"volume":38067,"mainPrice":3871.61},{"time":1552348800,"open":3871.61,"high":3905.2,"low":3826.06,"close":3882.73,"volume":26921,"mainPrice":3882.73},{"time":1552435200,"open":3882.69,"high":3893.56,"low":3840,"close":3866,"volume":24461,"mainPrice":3866},{"time":1552521600,"open":3866,"high":3920,"low":3810.43,"close":3877.12,"volume":27049,"mainPrice":3877.12},{"time":1552608000,"open":3877.12,"high":3939.22,"low":3872.2,"close":3923.76,"volume":21740,"mainPrice":3923.76},{"time":1552694400,"open":3924.46,"high":4056.98,"low":3921.98,"close":4005.98,"volume":28568,"mainPrice":4005.98},{"time":1552780800,"open":4005.98,"high":4012,"low":3950.01,"close":3981.14,"volume":18814,"mainPrice":3981.14},{"time":1552867200,"open":3981.85,"high":4037,"low":3953.33,"close":3987.81,"volume":22454,"mainPrice":3987.81},{"time":1552953600,"open":3987.83,"high":4031,"low":3970,"close":4015.53,"volume":19894,"mainPrice":4015.53},{"time":1553040000,"open":4017.48,"high":4050,"low":3980.5,"close":4043.04,"volume":23432,"mainPrice":4043.04}]';
let quotes = JSON.parse(json);
let quotesCount = quotes.length;

let renkoOriginalData = {
	ticker: "TICKER",
	timestamp: [],
	open: [],
	high: [],
	low: [],
	close: [],
	volume: [],
};
for (let i = 0; i < quotesCount; i++) {
	renkoOriginalData.timestamp.push(parseInt(quotes[i].time));
	renkoOriginalData.open.push(quotes[i].open);
	renkoOriginalData.high.push(quotes[i].high);
	renkoOriginalData.low.push(quotes[i].low);
	renkoOriginalData.close.push(quotes[i].close);
	renkoOriginalData.volume.push(quotes[i].volume);
}

let renko = new technicalIndicators.renko(Object.assign({}, renkoOriginalData, { brickSize: 10, useATR: false }));

let chartCandlesticks = [];
for (let i = 0; i < renko["open"].length; i++) {
	chartCandlesticks.push({
		time: renko["timestamp"][i],
		open: renko["open"][i],
		high: renko["high"][i],
		low: renko["low"][i],
		close: renko["close"][i],
	});
}

// plotting the chartCandleSticks

Why do I get such strange shadows?

[ProgrammingLife]

If I use just for testing purposes this: let renko = new technicalIndicators.HeikinAshi(renkoOriginalData).result;

all works fine. Shadows place in the right places. Looks like the issue only with the Renko chart type. Is this my fault?