Examine source code of Squabbles QOL

{
  "manifest_version": 2,
  "name": "Squabbles QOL",
  "version": "1.5.3",
  "description": "Squabbles.io quality of life features",
  "icons": {
    "48": "icon.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://squabbles.io/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "main.css"
      ]
    }
  ],
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "*://squabbles.io/*"
  ],
  "applications": {
    "gecko": {
      "id": "squabbles@spidey"
    }
  }
}