Examine source code of Clear Glass

{
  "manifest_version": 2,
  "name": "__MSG_extName__",
  "description": "__MSG_extDescription__",
  "version": "1.3.1",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "default_locale": "en",
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "stephen.anthony.rivas@gmail.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "strict_min_version": "142.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Clear Glass",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.glassdoor.at/*",
        "https://*.glassdoor.be/*",
        "https://*.glassdoor.ca/*",
        "https://*.glassdoor.ch/*",
        "https://*.glassdoor.co.in/*",
        "https://*.glassdoor.co.nz/*",
        "https://*.glassdoor.co.uk/*",
        "https://*.glassdoor.com.ar/*",
        "https://*.glassdoor.com.au/*",
        "https://*.glassdoor.com.br/*",
        "https://*.glassdoor.com.hk/*",
        "https://*.glassdoor.com.mx/*",
        "https://*.glassdoor.com/*",
        "https://*.glassdoor.de/*",
        "https://*.glassdoor.es/*",
        "https://*.glassdoor.fr/*",
        "https://*.glassdoor.ie/*",
        "https://*.glassdoor.it/*",
        "https://*.glassdoor.nl/*",
        "https://*.glassdoor.sg/*",
        "https://*.repvue.com/*",
        "https://*.teamblind.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/content.js"
      ]
    },
    {
      "matches": [
        "https://*.glassdoor.at/*",
        "https://*.glassdoor.be/*",
        "https://*.glassdoor.ca/*",
        "https://*.glassdoor.ch/*",
        "https://*.glassdoor.co.in/*",
        "https://*.glassdoor.co.nz/*",
        "https://*.glassdoor.co.uk/*",
        "https://*.glassdoor.com.ar/*",
        "https://*.glassdoor.com.au/*",
        "https://*.glassdoor.com.br/*",
        "https://*.glassdoor.com.hk/*",
        "https://*.glassdoor.com.mx/*",
        "https://*.glassdoor.com/*",
        "https://*.glassdoor.de/*",
        "https://*.glassdoor.es/*",
        "https://*.glassdoor.fr/*",
        "https://*.glassdoor.ie/*",
        "https://*.glassdoor.it/*",
        "https://*.glassdoor.nl/*",
        "https://*.glassdoor.sg/*",
        "https://*.repvue.com/*",
        "https://*.teamblind.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/early-dom-guard.js"
      ],
      "world": "MAIN"
    }
  ]
}