The source’s Android build found the same class in two artifacts:
* What went wrong:
Execution failed for task ':app:checkDebugDuplicateClasses'.
> 1 exception was raised by workers:
java.lang.RuntimeException: java.lang.RuntimeException: Duplicate class com.google.common.util.concurrent.ListenableFuture found in modules guava-20.0.jar (com.google.guava:guava:20.0) and listenablefuture-1.0.jar (com.google.guava:listenablefuture:1.0)The recorded change selected an Android Guava artifact:
implementation 'com.google.guava:guava:28.2-android'That is evidence of the earlier project’s resolution, not a universal dependency rule. Inspect which paths introduce Guava and the standalone listenablefuture artifact, then verify the resolved graph and runtime requirements.
The old version is retained intentionally; this revision does not upgrade or rebuild an Android project.