At master 7926b28, PagerView installs its proxy only when originalDelegate is nil. Changing the children count recreates the TabView; if the previous original delegate remains alive, the new collection never receives the proxy, and forwarding still targets the previous original. An actual UIKit Simulator harness reproduces four replacement/forwarding failures plus two separate proxy contract failures: responds(to:) omits NSObject selectors when no original exists, and zero-sized scroll callbacks are not forwarded. Proposed focused fix: restore the previous collection delegate when replacing it, install based on current delegate identity, always preserve original forwarding, and include superclass selector support. This concerns the current SwiftUI implementation, not the legacy UIPageViewController cleanup in PR #1040. This source audit is AI-assisted.
At master 7926b28, PagerView installs its proxy only when originalDelegate is nil. Changing the children count recreates the TabView; if the previous original delegate remains alive, the new collection never receives the proxy, and forwarding still targets the previous original. An actual UIKit Simulator harness reproduces four replacement/forwarding failures plus two separate proxy contract failures: responds(to:) omits NSObject selectors when no original exists, and zero-sized scroll callbacks are not forwarded. Proposed focused fix: restore the previous collection delegate when replacing it, install based on current delegate identity, always preserve original forwarding, and include superclass selector support. This concerns the current SwiftUI implementation, not the legacy UIPageViewController cleanup in PR #1040. This source audit is AI-assisted.