Solved: kind of. We have a custom property wrapper that implements DynamicProperty to enable remote feature flagging directly in SwiftUI views. We were using this to remotely enable dark mode. Even though the feature flag was turned on, something about the way this dynamic property wrapper works was causing the view to not set the correct mode on first launch, even when the value changes. We've not had any problems with this property wrapper in other views. Rather than waste more time trying to figure it out, we decided to simply remove the feature flag around dark mode and ship it directly.

A few things I've tried and a few more observations: Re-adding Appearance to the Info.plist with a value of "Automatic" does not fix the issue. Updating from previous version to new version doesn't work. Downgrading back to previous version and then updating to new version again does cause the change to be picked up. Updating from one build of the new version to another build of the new version also seems to cause the change to be picked up. Giving WindowGroup an explicit id to see if that causes the session to be rebuilt - this does not work either.

I can confirm that as of Xcode 14.1b2 that coverage for selected targets on an SPM package library is now working as expected on my Intel iMac Pro but continues to show no coverage on my M1 Max MBP.