Websocket getting cut off when working with CallKit API, iOS 17.5 and higher

[seoplague]

Before the iOS 17.5 update, calling worked relatively stable. However, starting from this version and on, Safari instantly force-closes all open websocket connections when the "Answer" button on the calling UI is hit. So, basically, the call ends right after it answers, because in our case websockets are crucial for the SIP negotiation process.

Firstly, I inspected the Safari console, and there is a new red error saying: WebSocket connection to 'wss://home.thirdlane.com/wss' failed: The operation couldn’t be completed. Software caused connection abort.

Secondly, I checked the Xcode logs, and there are several warnings saying Invalidating grant <invalid NS/CF object> failed every time the call is answered.

@mattkhaw Maybe you also encountered this problem after upgrading to 17.5 and found a solution to this problem?