Examine source code of Highlight Jumping

{
  "name": "Highlight Jumping",
  "author": "Yanying Wang",
  "version": "0.4",
  "homepage_url": "https://github.com/yanyingwang/highlight-jumping",
  "description": "highlight target text when clicking a hash link and jumping.",
  "page_action": {
    "browser_style": true,
    "default_title": "Highlight Jumping",
    "default_icon": {
      "16": "images/icon-16.png",
      "32": "images/icon-32.png",
      "48": "images/icon-48.png",
      "128": "images/icon-128.png"
    },
    "show_matches": [
      "https://docs.racket-lang.org/*",
      "file:///*racket*doc*",
      "file:///Applications/Racket%20v*/*",
      "file:///Users/*/*/docs/*",
      "https://github.com/*",
      "https://gitlab.com/*",
      "https://stackoverflow.com/*",
      "https://www.rubydoc.info/*",
      "https://sequel.jeremyevans.net/rdoc/*",
      "https://*.wikipedia.org/*",
      "https://racket.discourse.group/*"
    ]
  },
  "icons": {
    "16": "images/icon-16.png",
    "32": "images/icon-32.png",
    "48": "images/icon-48.png",
    "128": "images/icon-128.png"
  },
  "content_scripts": [
    {
      "js": [
        "content_script.js"
      ],
      "matches": [
        "https://docs.racket-lang.org/*",
        "file:///*racket*doc*",
        "file:///Applications/Racket%20v*/*",
        "file:///Users/*/*/doc/*",
        "https://github.com/*",
        "https://gitlab.com/*",
        "https://stackoverflow.com/*",
        "https://www.rubydoc.info/*",
        "https://sequel.jeremyevans.net/rdoc/*",
        "https://*.wikipedia.org/*",
        "https://racket.discourse.group/*"
      ]
    }
  ],
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "{0a5203da-7911-4ba7-83ea-a300906e071b}"
    }
  }
}