I am unable to use Xhr formData to upload files with Safari on MacOS 10.12. It never hits my web services. It acts as if it just hangs. The request never gets sent nor does it return a response. Chrome and Firefox still work fine as do previous versions of OSX. Did something change in Sierra?
To make matters even more strange. If I startup Fiddler to inspect the request and switch to an unsecure/http connection, the request goes through and hits my web service. Without Fiddler running, an unsecure connections behaves the same....nothing happens and the request never makes it through.
Any ideas?