Examine source code of Copy and Visit

{
  "manifest_version": 2,
  "name": "CopyAndVisit",
  "version": "1.0.0",
  "description": "Copies one or multiple links and marks them as visited",
  "icons": {
    "48": "download-48.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "clipboardWrite",
    "contextMenus",
    "history"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": true,
      "js": [
        "openlinks_content.js"
      ]
    }
  ]
}