UMG Retainer Box issue with Opacity

Hello there,

I get an issue with the Retainer Box where it’s Opacity behaves strange (4.19 - 4.25.3). I found a question on the Answerhub which is a bit similar but not the same issue like mine.

This screen shows the issue (2 borders, both with the same color/opacity, right one rendered with RB, the left one not). As you can see, the border rendered with the retainer box has another opacity.

This screen shows the setup in UMG:

This screen shows the RB Blend Material, I am pretty sure that it has something to do with the material output, but I can not figure out what I’m doing wrong:

This is the blend without Material:

Does anyone have an idea? Thanks in advance!

Did you read the tooltip for Effect Material? Maybe that’s what you’re doing wrong?