Examine source code of SFDC Content Copier

{
  "manifest_version": 3,
  "name": "Salesforce Case Copier",
  "version": "1.0.0",
  "description": "Copy Salesforce case content to clipboard with one click",
  "permissions": [
    "scripting",
    "clipboardWrite"
  ],
  "host_permissions": [
    "https://*.salesforce.com/*",
    "https://*.lightning.force.com/*"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_title": "Salesforce Case Copier"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.salesforce.com/*",
        "https://*.lightning.force.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "alexcwn@gmail.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}