Examine source code of Strava, export gpxaq

{
  "manifest_version": 2,
  "version": "1.3.2",
  "name": "Strava, export gpx track",
  "homepage_url": "http://e-ivanov.ru/projects/strava-export-gpx/",
  "description": "Export gpx-track from strava.com (c) Eugene Ivanov, 2016",
  "content_scripts": [
    {
      "all_frames": true,
      "js": [
        "data/includes/jquery-3.2.1.min.js",
        "data/includes/sugar-custom.js",
        "data/includes/main.js"
      ],
      "css": [],
      "matches": [
        "*://*.strava.com/*"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "*://*.strava.com/*"
  ],
  "content_security_policy": "script-src 'self'; object-src 'self';",
  "icons": {
    "16": "data/icons/icon_16.png",
    "128": "data/icons/icon_128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d7f99193-8105-49c1-a4d7-2e45e2ba45d3}"
    }
  }
}