The difference between the %J and that of the is that it is plotted as a histogram and the second being that the value are weighted and as such delivers more emphasis on the shorter term %K line.
What we now have is a line that moves quite slowly and has the knack to move beyond the range of a normal indicator.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.