This is incredible work, thanks to the whole Plotly team ! 
Just a small question about the area trace type that has been dropped in 5.0 : what would be the most efficient way to reproduce such a graph ?
It is mentioned in the forum here to use barpolar trace type, but it seems to me that barpolar trace is still different from a pure area trace type.
Below an area chart in one of my apps I had coded with px.area with Plotly 4.14.3 :

Thanks in advance ! Cheers.