FluentU Japanese Furigana

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "FluentU Japanese Furigana",
  "description": "Display corresponding hiragana characters above kanji on FluentU",
  "version": "3.1",
  "manifest_version": 2,
  "icons": {
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.fluentu.com/japanese/learning/*"
      ],
      "js": [
        "script.js"
      ],
      "css": [
        "style.css"
      ]
    }
  ]
}