Examine source code of Little Brother

{
  "name": "Little Brother",
  "version": "2021.51",
  "description": "An extension to balance items quantities during sales in Lightspeed Retail",
  "permissions": [
    "activeTab",
    "https://*.merchantos.com/*",
    "https://*.lightspeedapp.com/*",
    "https://xkcd.com/*",
    "webRequest",
    "storage",
    "tabs",
    "webRequestBlocking"
  ],
  "options_ui": {
    "page": "options.html"
  },
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "web_accessible_resources": [
    "Resources/sweetalert2.js"
  ],
  "content_scripts": [
    {
      "js": [
        "Resources/jquery-3.5.1.js",
        "Resources/semantic.js",
        "Resources/sweetalert2.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_idle",
      "all_frames": false
    },
    {
      "js": [
        "contentScript.js"
      ],
      "matches": [
        "https://*.merchantos.com/*",
        "https://*.lightspeedapp.com/*"
      ],
      "run_at": "document_start",
      "all_frames": false
    }
  ],
  "background": {
    "scripts": [
      "balanceSale.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "Images/favicon-16_x_16.png",
      "32": "Images/favicon-32_x_32.png",
      "48": "Images/favicon-48_x_48.png",
      "128": "Images/favicon-128_x_128.png"
    }
  },
  "icons": {
    "16": "Images/favicon-16_x_16.png",
    "32": "Images/favicon-32_x_32.png",
    "48": "Images/favicon-48_x_48.png",
    "128": "Images/favicon-128_x_128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "littlebrother@lightspeed.com"
    }
  },
  "manifest_version": 2
}