Examine source code of Wikipedia Peek

{
  "manifest_version": 2,
  "name": "Wikipedia Peek",
  "short_name": "Wikipedia Peek",
  "version": "2.7.4resigned1",
  "author": "Niklas Gollenstede",
  "license": "MPL-2.0",
  "description": "Browser extension that shows previews of linked articles on Wikipedia pages",
  "repository": {
    "type": "git",
    "url": "https://github.com/NiklasGollenstede/wikipedia-peek"
  },
  "icons": {
    "512": "icon.svg"
  },
  "minimum_chrome_version": "55.0.0",
  "applications": {
    "gecko": {
      "id": "@wikipedia-peek",
      "strict_min_version": "52.0"
    }
  },
  "permissions": [
    "storage",
    "notifications",
    "tabs",
    "webNavigation",
    "*://*/*"
  ],
  "optional_permissions": [],
  "web_accessible_resources": [],
  "incognito": "spanning",
  "background": {
    "page": "background/index.html"
  },
  "options_ui": {
    "page": "node_modules/web-ext-utils/options/editor/inline.html",
    "open_in_tab": false
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.wikipedia.org/*",
        "*://*.mediawiki.org/*",
        "*://*.wikia.com/*"
      ],
      "match_about_blank": false,
      "all_frames": false,
      "run_at": "document_end",
      "js": [
        "node_modules/es6lib/require.js",
        "node_modules/es6lib/concurrent.js",
        "node_modules/es6lib/dom.js",
        "node_modules/es6lib/functional.js",
        "node_modules/es6lib/namespace.js",
        "node_modules/es6lib/network.js",
        "node_modules/es6lib/object.js",
        "node_modules/es6lib/string.js",
        "node_modules/es6lib/index.js",
        "node_modules/web-ext-utils/browser/index.js",
        "node_modules/web-ext-utils/options/index.js",
        "common/options.js",
        "content/index.js"
      ]
    }
  ]
}