Examine source code of Copy All Links is

{
  "manifest_version": 2,
  "name": "Copy All Links",
  "version": "1.0",
  "description": "Copy all links from the current page to your clipboard",
  "permissions": [
    "activeTab",
    "clipboardWrite"
  ],
  "browser_action": {
    "default_icon": {
      "16": "icon.png"
    },
    "default_title": "Copy All Links"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e0e649c0-c090-4877-85e1-c1e62725a894}"
    }
  }
}