Particle Screen Alignment PSA Facing Camera Direction incorrect.

I have created a ribbon particle and a material that has a vertex normal node fed into emissive (translucent, default lit, 1 opacity).
I have the ribbon particle’s Screen Alignment (under Emitter) set to PSA Facing Camera Position.
The hover text for that value reads “Faces the camera position, but is not dependent on the camera rotation.”

Yet if I rotate the camera (without moving it) the colour of the particles changes, it would appear that the particles’ normals are always facing the opposite direction to the direction that the camera is facing (- camera rotation).

Hi Griffork -

Thank you for your report. I was able to replicate the issue internally and have reported the issue for further investigation by our engineers, for reference UE-22065. As soon as we have any further information I will report back to you here.

Thank You

Eric Ketchum