Examine source code of Elm Package Info

{
  "manifest_version": 2,
  "name": "Elm Package Info",
  "version": "1.11",
  "description": "Display additional information for a package on package.elm-lang.org (install command, license, dependencies, …)",
  "icons": {
    "16": "icons/elm-16.png",
    "48": "icons/elm-48.png",
    "128": "icons/elm-128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://package.elm-lang.org/*",
        "https://old.elm.dmy.fr/*"
      ],
      "js": [
        "package.js"
      ]
    }
  ],
  "permissions": [
    "tabs"
  ]
}