Examine source code of Vim nav

{
  "manifest_version": 2,
  "name": "vim_nav_plugin",
  "version": "1.1.0",
  "description": "Simple browser navigation shortcut like in vim j - k, alias feature & disable extension on custom domain.",
  "homepage_url": "https://github.com/aloisleclet/vim_nav_ext",
  "icons": {
    "48": "./icons/icon48.png",
    "96": "./icons/icon96.png",
    "128": "./icons/icon128.png",
    "256": "./icons/icon256.png",
    "500": "./icons/icon500.png"
  },
  "browser_action": {
    "default_icon": "./icons/icon96.png",
    "default_title": "vim navigation",
    "default_popup": "popup/index.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "webNavigation",
    "storage",
    "tabs",
    "*://*/*"
  ]
}