CORS preflight does not always send OPTIONS

Issue #9058564 • Assigned to Scott W.


Alex L.
Sep 25, 2016
This issue is public.
Found in
  • Microsoft Edge
  • Internet Explorer
Reported by 1 person

Sign in to watch or report this issue.

Steps to reproduce

When sending cross-origin XHRs inside Web Workers, sometimes only GET is sent without the pre-flight OPTIONS request, and thus failed to retrieve any resources as a result.


0 attachments

    Comments and activity

    • Microsoft Edge Team

      Changed Assigned To to “Brad E.”

    • Updated with October 2016 patches, of the ~2000 XHRs sent cross-origin, ~100 of them end up sending a direct GET without OPTIONS (and failed).

      I have also noticed that even for same-origin XHR, sometimes the browser would send GET request without any custom headers supplied manually.

    • Microsoft Edge Team

      Changed Assigned To to “Rico M.”

      Changed Assigned To to “Venkat K.”

      Changed Assigned To from “Venkat K.” to “Scott W.”

    You need to sign in to your Microsoft account to add a comment.

    Sign in