Xcode 11.4 compile error 'Missing package product <package name>'

When I integrate a local package in my Xcode project everything is fine initially but when i switch branches and want to run the app Xcode gives me the compile error Missing package product <package name>. When I quit Xcode and re-open it everything is fine again. Any idea what this can be? An Xcode bug?

We also integrate external packages via Swift Package Manager which works perfectly fine. No issues there.

The issue is also well described in a post by Jesse Squires.

Solution 1: File > Swift Packages > Reset Package Caches

Solution 2: File > Swift Packages > Update to Latest Package Versions