I have also been facing a similar issue, but never had the chance to test it in 17.3. Our app allows a user to scan a room and then save that scan on a separate view, followed by additional scans. We're looking into allowing room combining via CapturedStructure, so we need rooms to be scanned in the same ARWorldMap without necessarily needing to re-localize in the same session. This bring us to this issue - the only way I have found that allows our requirements is to save RoomCaptureView and to re-use that RoomCaptureView whenever we need to start a session again. This creates a number of other issues, and ideally, we wouldn't need to save a View in something like a singleton. We are using captureSession.stop(pauseARSession: false). Saving the ARSession and using it in let roomCaptureView = RoomCaptureView(frame: viewBounds, arSession: arSession) where we're creating a new view with the same ARSession seems much more ideal, but just like this issue stated, world tracking seems to be completely lost when a new RoomCaptureView (and thus a new RoomCaptureSession) is started, even with the same already started ARSession. Is there any way around needing to use the same RoomCaptureView or RoomCaptureSession for subsequent scans in the same session without needing to re-localize via ARWorldMap loading?