Examine source code of MultiView-ext

{
  "manifest_version": 2,
  "name": "MultiView",
  "version": "1.1.0",
  "description": "Watch up to 32 videos simultaneously in a grid overlay",
  "permissions": [
    "storage",
    "contextMenus",
    "activeTab",
    "*://*.youtube.com/*",
    "*://*.twitch.tv/*",
    "https://extensionpay.com/*"
  ],
  "background": {
    "scripts": [
      "src/shared/ExtPay.js",
      "src/shared/license.js",
      "src/background/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*",
        "*://*.twitch.tv/*",
        "<all_urls>"
      ],
      "js": [
        "src/shared/storage.js",
        "src/shared/grid-engine.js",
        "src/shared/sites/youtube.js",
        "src/shared/sites/twitch.js",
        "src/shared/sites/generic.js",
        "src/content/grid-overlay.js",
        "src/content/content.js"
      ],
      "css": [
        "src/content/content.css",
        "src/content/grid-overlay.css"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "https://extensionpay.com/*"
      ],
      "js": [
        "src/shared/ExtPay.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_action": {
    "default_popup": "src/popup/popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "commands": {
    "toggle-grid": {
      "suggested_key": {
        "default": "Alt+M",
        "mac": "Alt+M"
      },
      "description": "Toggle MultiView grid overlay"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "multiview@extension",
      "data_collection_permissions": {
        "required": [
          "personallyIdentifyingInfo",
          "financialAndPaymentInfo"
        ]
      }
    }
  }
}