Examine source code of Wikicopylink

{
  "manifest_version": 2,
  "name": "Wikicopylink",
  "version": "1.0",
  "description": "Adds a copy link button next to each section title on Wikipedia.",
  "applications": {
    "gecko": {
      "id": "@wikicopylink",
      "strict_min_version": "55.0"
    }
  },
  "icons": {
    "48": "icons/wikicopylink-48.png",
    "96": "icons/wikicopylink-96.png",
    "128": "icons/wikicopylink-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.wikipedia.org/*"
      ],
      "js": [
        "wikicopylink.js"
      ]
    }
  ]
}