Someone once asked me for a similar extension:
com.sunny.CornerRadius.aix (5.6 KB)
MIT can redistribute this extension:
I, vknow360 aka Sunny Gupta, attest that I am the author of the CornerRadius extension , grant that the extension included in this project is free and that MIT has a non-exclusive irrevocable license to republish the extension as part of the project file for the purposes of the MIT App Inventor Appathon 2023.