Examine source code of pass-browser

{
  "author": "Cornelis Poppema",
  "manifest_version": 2,
  "icons": {
    "128": "images/icon-locked-128.png"
  },
  "browser_action": {
    "default_icon": "images/icon-locked-128.png",
    "default_popup": "html/popup.html",
    "browser_style": false
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/content.js"
      ]
    }
  ],
  "permissions": [
    "<all_urls>",
    "activeTab",
    "clipboardWrite",
    "notifications",
    "storage"
  ],
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "options_ui": {
    "page": "html/options.html",
    "chrome_style": false,
    "browser_style": false
  },
  "applications": {
    "gecko": {
      "id": "pass-browser@web-extensions"
    }
  },
  "name": "pass-browser",
  "version": "0.8.1",
  "description": "Make secrets easily accessible from your pass' ~/.password-store"
}