To reproduce:

1. Enable Editor Profiling.
2. Enter Playmode, profile a bit,
3. Stop Profiling.
4. Exit Playmode.
5. In (Raw) Hierarchy select e.g. Profiler.DataDeserializer, and find Semaphore.WaitForSignal there.
6. Enable Profiling again.
7. Click on something in graph in CPU Usage.
8. Errors fail:
Missing Profiler.EndSample (BeginSample and EndSample count must match): ProfilerFrameDataTreeView.MigrateSelectedState) .

Actual result:
You're locked in Profiler.DataDeserializer view.
Whatever you do next - enter playmode, change views - you're always there. See screenshot.