I am also running into this error. (Jan 2026) Xcode v26.2. Icon Composer 1.2 (76) Looking at the release notes above, the issue has not been resolved. Error message I get: "Invalid large app icon. The app icon in the asset catalog -app name- can't be transparent or contain an alpha channel." My two cents, it might be due to the automated compiler for the apple App Store distribution SDK they use to review apps quickly before it goes to a real person. This might be due to the new Liquid Glass UX/UI update. I was really excited to try it, but until it gets fixed, I don't think we will get app icons being Liquid Glass anytime soon. Might be due to the fact that, I have the lowest version of iOS 17, which might not recognize it yet. I wonder if it is only for iOS 26 uploads? no idea.

I have also been getting this exact same problem.

has anyone been able to figure this out yet? I am still stuck.

I just submitted my today manually. will let you know if my app gets published to the App Store in the next day or so.