Purpose - MACD is an awesome indicator. However, I felt I could improve the existing MACD indicator by also letting it visualize the rate of change (ROC) of the histogram (whether rate of change is increasing or decreasing - just like a derivative). By doing so, the indicator will better show the rate of change of the trend.
How It's Done - To the original MACD indicator, I have added a bit more conditional statements that automatically calculates the ROC in MACD histogram and visualizes through 8 different colors.
Interpretation - While the histogram is above 0, darker color indicates the stronger up trend, and lighter the color, weaker the up trend and potentially indicates the bears are overtaking, and vice versa for the case where the histogram is below 0.