Conditional Shadow

If this toggle is enabled, a drop shadow effect will be applied to the series name in the tooltip. 

This feature can be used to avoid possible visibility issues when using the Dynamic Color in Tooltip setting, ensuring legibility in cases where conditional formatting may apply poorly contrasting colors (like yellow or lime green on a white tooltip, or indigo blue on a Dark Mode tooltip). 

Enabling this feature will reveal additional customization options for the shadows:
This setting will take effect only if the selected Tooltip Type is Custom Tooltip.