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Web Worker Failing on Chrome

See original GitHub issue

Chrome 75.0.3770.100 Win 10 64-bit

I do the following:

var compressionOptions = {
          maxSizeMB: 0.8,
          maxWidthOrHeight: 1920,
          useWebWorker: true,
          exifOrientation: true
const imageFile = await imageCompression(

and get the following in browser console:

browser-image-compression.mjs:430 Run compression in web worker failed: x is not defined , fall back to main thread

Any ideas what could be wrong? The image is correctly compressed, but without a web worker.

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:7 (2 by maintainers)

github_iconTop GitHub Comments

FaizanZahidcommented, Aug 5, 2019

@Donaldcwl i m having an issue when my browser adblock on chrome is turned ON , i get this error in console.

Refused to create a worker from ‘blob:’ because it violates the following Content Security Policy directive: “script-src ‘self’ * ‘unsafe-inline’”. Note that ‘worker-src’ was not explicitly set, so ‘script-src’ is used as a fallback.

(anonymous) @ browser.img.compress.js:1 (anonymous) @ browser.img.compress.js:1 (anonymous) @ browser.img.compress.js:1 (anonymous) @ browser.img.compress.js:1 browser.img.compress.js:1 Uncaught DOMException: Failed to construct ‘Worker’: Access to the script at ‘blob:’ is denied by the document’s Content Security Policy. at at at at

Any way to fix this, i have even turned off use web worker option by false.

Donaldcwlcommented, Mar 16, 2020

There should be no problem in v1.0.7

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