Interesting little bug here. When trading on the charts with something that has a value LESS than 0.00001, it will automatically default to 0.00001 and will not let you add more decimals. However, when something is above 0.00001, you actually CAN add more decimals by dragging ONLY, if you try to edit the value explicitly, it will cap it at 0.00001 and you can't add more decimals or use the up/down arrows. I have attached two screenshots showing a trade with < 0.00001 (#POE.BTC:BINANCE) and one with just above 0.00001 (#XVG.BTC:BINANCE):