Hi there @levko.
I don’t think that’s the correct behaviour a secondary y axis should have. Why would you want a data series to entirely cover up other data series?
The objective of a secondary y axis is to allow very different rangesof values to be plotted on the same graph.
For instance, on google sheets with the same data, when you go from 1 to 2 y axis’ you get:
1 y axis
2 y axis’
As you can see you get a better visualization into your data when using very different data ranges.