Examine source code of Tracking Token Stripper

{
  "name": "Tracking Token Stripper",
  "version": "2.12",
  "manifest_version": 2,
  "author": "Jon Parise",
  "description": "Removes Google Analytics (UTM) parameters, and various other click tracking tokens, from URL query strings.",
  "homepage_url": "https://github.com/jparise/chrome-utm-stripper",
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "https://*/*?*",
    "http://*/*?*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9fda17be-849d-4f5b-a326-28d25f0f6d29}"
    }
  }
}