Flowcard_not_registered on Walli Dimmer

I have the new Fibaro Walli Dimmer using the version 2.1.38 of the Fibaro app that has support for it.
Switching on/of and dimming the lights function as expected, but there’s also a flowcard “Led color when off” that can be set to several colors (or off).

When I make a flow using this flow card in the THEN part, it will display a red triangle with an exclamation mark on the flowcard and ticking the red triangle shows a red message for a short time indicating flowcard_not_registered.

I’m also going to report this to Athom since it looks to me to be something Athom needs to fix or am I wrong?

Edit: confirmed by Athom, now sent to developers.