UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.0 Safari/605.1.15

Example URL:
you would need an account on our service first since we are restricting access with cloud front signed cookies.

Steps to reproduce the problem:
See this - https://discourse.threejs.org/t/inconsistent-behavior-of-cors-policy/4208

1. Put image on aws S3
2. Create a cloud front bistro for the bucket
3. Create img element and point it to cloud front link.
4. set the crossorigin property of the img element appropriately (either "anonymous" or "with-credentials" - I have both - local testing and production environment - respectively)
4. Run 

What is the expected behavior?
The img element should load the url with no problems

What went wrong?
The img element after some time will stop loading the img.  any repeated attempts to load the image will fail. On opening the console you'll see CORS failures about not getting cors failures with the error "No 'Access-Control-Allow-Origin' header is present on the requested resource.".   

Now open the javascript console and attempt to retrieve the content (reload the page) - and viola - everything works. 

Did this work before? No 

Chrome version: 	69.0.3497.100  Channel: n/a
OS Version: OS X 10.13.6
Flash Version: 

Tested on Firefox and it works 100% of the time.