Support request regarding missing params in Redirect URL and inconsistent Universal Link behavior on iOS 18.4

Thank you for sharing your post. Could you provide a simple sample or recording demonstrating that the code does not function correctly on iOS 18.4, while it was previously working and passing the parameter prior to iOS 18.3?

Have you attempted a test by adding the link with parameters using Notes, tapping and holding to open the app with the parameters, and verifying if it still works on iOS 18.4?

Would you be willing to open a bug report for this issue?

Once you open the bug report, please post the FB number here for my reference.

If you have any questions about filing a bug report, take a look at Bug Reporting: How and Why?

Albert Pascual
  Worldwide Developer Relations.

Thank you very much for your response. I have submitted a bug report via Feedback Assistant. Please continue to support us through the following link: https://feedbackassistant.apple.com/feedback/17158745

Best regards,

Hanh Vu

I will note the feedback ID here : FB17158745 ([Error] Missing parameters in redirect URL when using SFSafariViewController on iOS 18.4 and above)

Thank you!

@vuhanh

Thanks for the FB number, noted and I'll keep an eye for a quick resolution. In the meantime:

You can see the status of your feedback in Feedback Assistant. There, you can track if the report is still being investigated, has a potential identifiable fix, or has been resolved in another way. The status appears beside the label "Resolution." We're unable to share any updates on specific reports on the forums.

For more details on when you'll see updates to your report, please see What to expect after submission.

Albert Pascual
  Worldwide Developer Relations.

Sorry for the inconvenience. It’s been a week, but I haven’t received any response from the support team. Our project is about to be released, and this issue is considered important. Therefore, we would really appreciate it if you could help us resolve it soon.

Thank you very much.

We are seeing the same issue. I checked and it still appears to be happening in iOS 26 beta 3.

I also opened a feedback request to report the issue. FB18860515

Different DTS Engineer here.

Thanks for those bug numbers. I was able to use them to track down some interesting info.

The iOS 18.4 change was a deliberate fix to address a security problem (r. 139228173). That’s caused issues for a number of developers and we’re still investigating what we can do to resolve it (r. 148942784). In the meantime, my advice is that you investigate whether it’s feasible to switch your authentication from SFSafariViewController to Authentication Services. If you can then that’ll get around this problem, and it’s a better long-term direction.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Thanks for the reply and the explanation Quinn. Our issue wasn't specifically with authentication, like the original post, but just with loosing the query parameters. But this gives me a direction to discuss with our product team for how to handle these urls for the time being. Hope that a resolution can be found soon though. Thank you again.