Examine source code of SubSubDeeCee

{
  "manifest_version": 2,
  "name": "SubSubDeeCee",
  "version": "1.1.6",
  "description": "Multilingual subtitles to WWDC videos",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{14d11436-34b3-4d84-b458-53bad54871ab}"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://developer.apple.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "96": "icon96.png",
    "128": "icon128.png"
  }
}