Can you trick this browser extension into revealing its data?

Challenge Information

This tiny browser extension is the keeper of a well-hidden secret. We would like to access it from our website, but the extension will only give it to mycompany.invalid which we don't own. Can you help us?

Note: The vulnerability is only exploitable in Google Chrome, not in Mozilla Firefox.

To try out the extension, unpack the ZIP file to a directory. Then go to chrome://extensions/, enable Developer mode, click "Load unpacked" and select the directory.

Challenge Solutions

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