Tooltip marker missing when fill type is gradient

[Hewsman]

Description

Steps to Reproduce

1. Create a chart
2. Set the fill type to gradient to have amazing color effects
3. Hover to trigger to tooltip

Expected Behavior

The tooltip should show the series color. either Solid color or gradient

Actual Behavior

Empty blank space

Screenshots

Reproduction Link

https://codepen.io/pgredigui/pen/JjLzNBv