Tempus Stopwatch 2021.2 is out. This version is a performance mitigation fix and does not include any new features. The app consumes a lot of CPU on certain Mac models. Thanks to all of you who sent angry bug reports ;-)
The root cause seems to be a SwiftUI and ScrollView/List. From what I can tell it's a known issue and may or may not be fixed by Apple. Feedback FB8983546.
I took advice from Paul Hudson and added a UUID to my list.
List {
}
.id(UUID())
This does not fix the problem. CPU usage is still high, but slightly less. Please Apple?