Setting collectionViewLayout somehow clear the cell class registrations, causing makeItem(withIdentifier:for:) to dequeue the cell from nib unexpectedly. This seems like a bug to me, so I fire a feedback FB14769347. As a workaround, set collectionViewLayout BEFORE calling your register(_:for:) methods.

Launchpad is still there in /System/Applications/, but hidden from Finder. You can still see it if you ls in terminal: ls /System/Applications/ You can still restore it by disabling the new Spotlight: sudo mkdir -p /Library/Preferences/FeatureFlags/Domain sudo defaults write /Library/Preferences/FeatureFlags/Domain/SpotlightUI.plist SpotlightPlus -dict Enabled -bool false Once reboot, you will see Launchpad in your Applications folder, but sacrifice the new Spotlight feature.