Examine source code of Email Reveal Protector

{
  "manifest_version": 2,
  "name": "Email Reveal Protector",
  "version": "1.1",
  "description": "Hide email addresses on pages until hover or click.",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d5803436-4fc4-4003-abc5-9d83b258e9d9}",
      "strict_min_version": "89.0"
    }
  },
  "icons": {
    "64": "icon64.png",
    "128": "icon128.png"
  }
}