TypeMismatchError occurred when opening a Blob URL using Fetch API

Fixed, not yet flighted Issue #7754905


Tomohito Y.
Jun 1, 2016
This issue is public.
Found in
  • Microsoft Edge
Found in build #
Reported by 3 people

Sign in to watch or report this issue.

Steps to reproduce

“TypeMismatchError” occurred when opening a Blob URL using Fetch API.


Fetch request has completed with no error.

Mozilla Firefox 48 and Google Chrome 52 works as expected.


Fetch throws "TypeMismatchError".

Repro code:

blob = new Blob(['Hello!Konnichiwa!'], { type: 'text/plain' });
// => [object Blob]{size: 17, type: "text/plain"}

blobUrl = URL.createObjectURL(blob);
// => "blob:ED2ABB1F-A1E4-4CF2-A61F-7FB643535A4F"

fetch(blobUrl).then(x => { console.log(x); return x.text(); }, e => console.log(e.message)).then(x => console.log(x))
// => [object Promise]{}
// => TypeMismatchError
// => undefined


Comments and activity

  • Microsoft Edge Team

    Changed Assigned To to “Venkat K.”

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

    Changed Assigned To from “Scott W.” to “Nicolas A.”

    Changed Assigned To from “Nicolas A.” to “Brandon M.”

    Changed Status to “Confirmed”

    Changed Status from “Confirmed” to “Fixed, not yet flighted”

  • We have a fix checked in to our dev branches - this should roll out to insiders first and then the public with future releases.  Thank you for the feedback on Edge.

  • Microsoft Edge Team

    Changed Status from “Fixed, not yet flighted” to “Fixed, flighted”

    Changed Status from “Fixed, flighted” to “Fixed, not yet flighted”

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

Sign in