Examine source code of TheatreModeChatLabelHider

{
  "manifest_version": 2,
  "name": "TheatreModeChatLabelHider",
  "version": "1.0",
  "description": "An extension that hides stream chat label on a twitch.",
  "icons": {
    "16": "icons/pants16.png",
    "48": "icons/pants48.png",
    "128": "icons/pants128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.twitch.tv/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{870d07db-f0fe-4b5b-8319-30e42382dab1}"
    }
  }
}