Examine source code of yt-declutter

{
  "manifest_version": 2,
  "name": "yt-declutter",
  "version": "1.1resigned1",
  "description": "Removes annoying recommendations from YT landing page",
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "yt-declutter.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9bceaa6a-23d6-4553-8936-ef462f4a25d6}"
    }
  }
}