Examine source code of Referee

{
  "name": "Referee",
  "version": "1.0.0",
  "manifest_version": 2,
  "description": "Remove tracking refs from URLs and copy them to your clipboard.",
  "icons": {
    "16": "referee-16.png",
    "48": "referee-48.png",
    "128": "referee-128.png"
  },
  "background": {
    "scripts": [
      "common.js"
    ]
  },
  "browser_action": {
    "default_icon": "referee-48.png",
    "default_title": "Referee",
    "default_popup": "popup.html",
    "browser_style": true
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Shift+Alt+C"
      }
    }
  },
  "permissions": [
    "activeTab",
    "clipboardWrite",
    "tabs"
  ]
}