Echo360 Closed Captions

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Echo360 Closed Captions",
  "description": "Add closed captions to Echo360 lectures!",
  "version": "1.6",
  "manifest_version": 3,
  "content_scripts": [
    {
      "matches": [
        "https://echo360.org/lesson/*",
        "https://echo360.org.uk/lesson/*",
        "https://echo360.org.au/lesson/*",
        "https://echo360.org.ca/lesson/*",
        "https://echo360.net/lesson/*",
        "https://echo360.net.uk/lesson/*",
        "https://echo360.net.au/lesson/*",
        "https://echo360.net.ca/lesson/*"
      ],
      "css": [
        "my-styles.css"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ],
  "background": {
    "service_worker": "background.js"
  },
  "permissions": [
    "storage",
    "scripting"
  ],
  "action": {
    "default_icon": {
      "16": "/images/closed_caption16.png",
      "32": "/images/closed_caption32.png",
      "48": "/images/closed_caption48.png",
      "128": "/images/closed_caption128.png"
    }
  },
  "icons": {
    "16": "/images/closed_caption16.png",
    "32": "/images/closed_caption32.png",
    "48": "/images/closed_caption48.png",
    "128": "/images/closed_caption128.png"
  }
}