Examine source code of cratehub

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  "manifest_version": 2,
  "name": "cratehub",
  "version": "0.0.3",
  "description": "github rust cargo project crates info",
  "browser_action": {
    "default_icon": "assets/icon-512.png"
  },
  "background": {
    "page": "background/index.html",
    "persistent": true
  },
  "icons": {
    "16": "assets/icon-512.png",
    "48": "assets/icon-512.png",
    "128": "assets/icon-512.png"
  },
  "permissions": [
    "https://crates.io/",
    "activeTab",
    "http://*/",
    "https://*/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "sveltesse-webext@fixme.com"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://github.com/*",
        "https://gitlab.com/*"
      ],
      "js": [
        "./contentScripts/index.global.js"
      ],
      "css": [
        "./contentScripts/style.css"
      ]
    }
  ],
  "web_accessible_resources": [
    "./contentScripts/style.css"
  ]
}