In my case was because I had some animations (UIView.animate...) since the framework needs to wait for the app to be static. What I did was UIView.setAnimationsEnabled(false) when running the app from the UI tests (you can send launchArguments or something)

This indicates that compositional layout is trying to resolve layout for a section that doesn't exist in the data source. This was the issue on my case, however my data source was returning the correct sections (like if the compositional layout had a cache), invalidating the layout worked for me: collectionView.collectionViewLayout.invalidateLayout()