I appreciate the detailed response and suggested work-around! Could you confirm the following statements I've concluded based on your reply: Scene preference is only applied to windows opened before the session is received. Simply put, all participants must have the window open before the initiator clicks the "Start [Activity]" button (that activates the activity) for SharePlay to associate them. It appears you are opening the recipient window after the session is received, but before the session is joined. Note: received is distinct from joined. The documentation for SceneAssociationBehavior mentions the scene modifier handlesExternalEvents(matching:), which is supposed to be for the app intercepting a group activity and opening the scene if it is currently not open. Should I take the above limitation to mean that this scene modifier is not properly working in regards to group activities/SharePlay? I have tested with another vision pro user having both the main window and the volume window (the targeted SharePlay window) open and the share menu did not update to show that it was sharing. So the work around essentially revolves around simply having a singular window group, but selectively showing/hiding content based on whether or not we have a GroupSession. Am I misunderstanding that the assumption here is that multiple window groups being defined (even if they are all volumetric windows as per the second limitation where the initial window style needs to match the SharePlay target window) currently does not work with SharePlay properly then? Ideally I would want to retain the multiple windows for display purposes, but will go ahead for now and see if the proposed work-around can somehow fit my use case. Again, I appreciate the detail!