Edit: Figured out what was causing it for me. I didn't have a sharing fallback URL (I assumed it was optional, being a fallback URL.) Without it, it won't know where to redirect the share. You can dig through the actual JS on the error page to see what it's doing when it's searching for an applicationIdentifier. Solution seems to be to set that to be a deep link + load the share when opened in app, or to have an intermediate site that tries to open it in the app. Has anyone had any success figuring out what's causing this? No share links I create in the simulator work. Even using apple's CloudKit + CoreData example, out of the box, I get this error when sharing links: APP NAME cloudos2 CLIENT TIME Fri Mar 11 2022 15:44:38 GMT-0500 (Eastern Standard Time) (1647031478196) USER AGENT Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:97.0) Gecko/20100101 Firefox/97.0 HOSTNAME www.icloud.com BUILD INFO 2208Project39__2208B28__en-ca SESSION ID 65f98416-8374-4878-a36e-0f3a9a5b4e5f ENVIRONMENT INFO PROD REPORTED ERROR TITLE ShareRecord: Unable to find applicationIdentifier for containerId = iCloud.MY.CONTAINER.IDENTIFIER and fileExtension = undefined REPORTED ERROR TYPE UNHANDLED_EXCEPTION LINE NUMBER 11 STACK r@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:88639 a@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:88690 _getApplicationIdentifier@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:421359 _extractCloudKitResponse@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:419260 init@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:417999 create@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:255839 resolveShortGuid/<@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:423970 r@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:461581 i@https://www.icloud.com/system/cloudos2/2208Project39/en-ca/main.js:11:194550 ERROR CONTEXT undefined