Examine source code of Force New Tab

{
  "manifest_version": 3,
  "name": "Force New Tab",
  "version": "1.3.0",
  "description": "Forces middle-click (MB3) on any element (including JavaScript buttons) to open the page in a new tab.",
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "force-new-tab@firefox",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}