No, i'm not speaking about transparency, i'm speaking about quick backdrop object that doesn't have transparency, they are just one color or gradient of two.
In previous version the back was showing as true black in the frame editor, now it uses the "legacy" fake black (0,0,8). But when the project is built, the color shown when running the app is the good one.
example.png
PS: This forum is getting worst each days, actually the HTTPS certificate seems outdated.