@shimastripe Thanks for the information. It is very helpful to know that similar behavior has also been observed with ASWebAuthenticationSession. We have not yet done enough testing specifically on iPadOS 27.0.1, but we subsequently tested on iPadOS 27.2 beta (24B5089g) / Safari 27.2, and the same Safari crash still reproduces. The crash does not occur immediately after launching Safari. It occurs when tapping a form field and bringing up the software keyboard. The crash log also shows a SIGABRT around TUIKeyplaneView prepareForSplitTransition, similar to what we observed previously. However, our additional testing has shown some interesting differences. On a retail/demo iPad mini (A17 Pro) running iPadOS 27.0: Amazon, Yahoo, Google, and Rakuten worked normally even after repeatedly terminating and relaunching Safari. Our own web app still crashed after Safari had been backgrounded or terminated and then relaunched, when a form field was focused. After reproducing the crash on our site, we tested Amazon and the other sites again, and they continued to work normally. In another test, Safari crashed when launched normally, while we could not reproduce the crash when Safari was opened together with Google Maps in Split View via a shortcut. So at this point, we still suspect an iPadOS / Safari issue, but it also appears possible that some page-specific condition makes the OS-level issue easier to trigger. We are continuing to investigate that interaction. If you have any additional details about the ASWebAuthenticationSession case, such as the exact reproduction conditions or crash logs, we would really appreciate it if you could share them.