Expected Behavior

With the new feature as integrated here:
openhab/openhab-core#4610
I would expect that with interpolation="step" you get steps, i.e. horizontal lines from the point where the value was recorded until the next point would be drawn in the BasicUI sitemap charts.

Current Behavior

It just shows the standard behavior as always.

See here:
openhab/openhab-core#4610 (comment)

Possible Solution

I think it is a bug, to be fixed.

Steps to Reproduce (for Bugs)

1. Configure a chart with any persistence data.
2. Use the interpolation="step" parameter and remove it. Chart won't change.

Context

The idea behind the new feature "step" is to create charts that directly reflect the manner openHAB is dealing with item changes: The old value is valid until the item is updated to a new value (state). This is especially useful if you have persistence data with non-uniform timings.
Therefore would be nice to get it working.

Your Environment

RasPi 4, 4GB, openHABian 64bit, openHAB 5.0.0.M4.