Examine source code of Fix Brain.FM

{
  "manifest_version": 2,
  "name": "Fix Brain.FM",
  "version": "1.0.3resigned1",
  "description": "Fixes malformed headers sent by brain.fm templates endpoint",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "https://www.brain.fm/"
  ],
  "background": {
    "scripts": [
      "bg.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{09b39ae1-5e7f-4dbb-a13c-6bc96bce16bd}"
    }
  }
}