Extension works in Incognito but errors out on new profile: “Cannot assign to read-only property ‘fetch’”

Request
1

Hi everyone,

I’ve just set up a brand-new machine and installed language reactor in Chrome.

Problem:

  • The extension runs correctly in Incognito mode or in another browser profile, but it fails completely in my main profile.
  • In the DevTools console I see:
Uncaught TypeError: Cannot assign to read-only property ‘fetch’ of object ‘#<Window>’  
    at pageScript_11y.min.js:4478:8192  
…  
GET https://rr4-sn-ntq2yned.googlevideo.com/videoplayback?… 403 (Forbidden)

What I’ve tried so far:

  1. Disabled all other extensions (in case of conflict).
  2. Cleared browser cache and cookies.
  3. Re-installed the extension.
  4. Verified it works fine in Incognito and in a temporary profile.

Questions:

  1. Why would the extension be able to override window.fetch in Incognito but not in my main profile?
  2. Is there a manifest or content-script setting I’m missing that allows me to patch fetch safely?
  3. Any pointers on how to work around this “read-only” error so that the extension can load properly?

Thanks in advance for any insights!

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