Examine source code of Emotes Anywhere

{
  "manifest_version": 2,
  "name": "Emotes Anywhere",
  "short_name": "Emotes",
  "version": "0.87",
  "content_scripts": [
    {
      "matches": [
        "*://www.youtube.com/*",
        "*://www.reddit.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "description": "Bring your favourite websites to life by adding this lightweight extension that enables Twitch emotes, exclusively to the comments",
  "author": "Rhenier Kloppers",
  "browser_action": {
    "default_icon": "emotesanywhere.png",
    "default_title": "Popup here."
  },
  "permissions": [
    "*://www.youtube.com/*",
    "*://www.reddit.com/*",
    "tabs"
  ]
}