Examine source code of AWS Signer Browser

{
  "name": "AWS Signer Browser",
  "description": "Automatically sign requests to AWS",
  "version": "0.2.2",
  "homepage_url": "https://github.com/Frederick888/aws-signer-browser",
  "manifest_version": 2,
  "applications": {
    "gecko": {
      "id": "aws-signer-browser@tsundere.moe"
    }
  },
  "icons": {
    "48": "icons/aws-48.png"
  },
  "permissions": [
    "storage",
    "notifications",
    "webRequest",
    "webRequestBlocking",
    "tabs",
    "*://*.amazonaws.com/*"
  ],
  "optional_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js",
      "node_modules/crypto-js/crypto-js.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "icons/aws-19.png",
      "38": "icons/aws-38.png"
    },
    "default_title": "AWS Signer",
    "default_popup": "popup/popup.html"
  }
}