Remap Top: Depth Source Parameter greyed out

Version 2023.12000 - Mac Silicon

The Depth Source Parameter becomes greyed out everytime I connect something to the Remap Top.

Im trying to utilize the Remap Top in order to create flow fields inside a Top based particle system. This is we’re I got the idea from. It works very well in a 2d context, but in order to project these flow fields on a 3d particle systems, I think I’d have to access to the Depth Source parameter.

When I right click the parameter to show the parameter help, there is also no help available. This makes me question whether this parameter is reserved for future versions, or whether its a problem on my side.

Anyway it’d be greatly appreciate it if someone could point me into the right direction. Thanks!