Examine source code of WaniKaniKeebi

{
  "manifest_version": 2,
  "name": "WaniKaniKeebi",
  "version": "1.0.2",
  "description": "Auto-expand WaniKani's Item Info pane when you submit an answer during reviews, because using a mouse is the worst.",
  "homepage_url": "https://github.com/carwin/WaniKaniKeebi",
  "icons": {
    "48": "icons/wkk-48.png"
  },
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.wanikani.com/*"
      ],
      "js": [
        "waniKaniKeebi.js"
      ]
    }
  ]
}