CORS Preflight OPTIONS request not sent in iOS Simulator

Capacitor
1

My app (Ionic 5 + Angular 11 + Capacitor 2.4.6) successfully communicates with my backend web service (RESTful + HTTPS) on a physical iPhone (running iOS 13.6), but it fails in the iPhone Simulator (both iOS 13.6 and iOS 14.3).

Using Safari Web Inspector the Network tab is missing an OPTIONS request, and then unsurprisingly reports “Failed to load resource: Preflight response is not successful” for the POST request.

The behavior is the same as described in [iOS 12 Beta] Preflight requests fail - #27 by kashif.jtech, but I’m using the latest versions of everything. Unlike that issue, this does not appear to be an iOS bug, since it works on the same iOS version on a physical device.

I haven’t been able to find anyone else experiencing the same problem, and I’m at a loss for what to try.

2

Nevermind. There was a bug in my backend code.

Safari Web Inspector does not show Preflight OPTIONS requests in the Network tab any more, and this is tracked under 213215 – Web Inspector: CORS preflight OPTIONS requests no longer shown in Network tab, but the requests are indeed sent.