BUG: InvalidOperation exception on stopping the project in the editor

[SimonDarksideJ]

May be nothing, but recording here to capture it. Encountered a collection modification exception on stopping the dev project in the editor:

InvalidOperationException: Collection was modified; enumeration operation may not execute.
System.Collections.Generic.HashSet`1+Enumerator[T].MoveNext () (at <f3cb625e9a3f437991ebaf58a99c81f7>:0)
RealityToolkit.Input.Interactables.Interactable.OnSourceLost (RealityToolkit.EventDatum.Input.SourceStateEventData eventData) (at ./Packages/com.realitytoolkit.core/Runtime/Input/Interactables/Interactable.cs:520)
RealityToolkit.Input.Handlers.InputServiceEventHandlers+<>c.<.cctor>b__43_1 (RealityToolkit.Input.Interfaces.Handlers.ISourceStateHandler handler, UnityEngine.EventSystems.BaseEventData eventData) (at ./Packages/com.realitytoolkit.core/Runtime/Input/Handlers/InputServiceEventHandlers.cs:36)

Unclear as to the cause of the event.