Do you use any framework for the charts? If no, why not? Wasn't it a lot of work?

Also, a bug (or maybe wanted feature) is that when there is a low volume (e.g. Kraken), if the chosen timeframe is e.g. 1 min and there isn't any trade during at least a whole minute then there will not be any space between the two candlesticks. Normal?

Put more simply, if you hover your mouse pointer over the candlesticks you may get 19:50, 19:51, 19:55 if there isn't any trades between 19:52:00 and 19:54:59.