Examine source code of PrecisionTouchPadSwipe

{
  "manifest_version": 2,
  "name": "PrecisionTouchPadSwipe",
  "version": "1.4.2",
  "description": "Enables two-finger swipe (backwards/forwards) in Firefox for Precision Touchpads. ",
  "icons": {
    "48": "icons/icon.png",
    "96": "icons/icon@2x.png"
  },
  "homepage_url": "https://github.com/selleronom/PrecisionTouchPadSwipe",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "swipe.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background-script.js"
    ]
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{635acc1b-7e70-485b-b483-d77befc884b4}",
      "strict_min_version": "57.0"
    }
  }
}