Examine source code of WebSmith's Arcanum

{
  "manifest_version": 2,
  "name": "WebSmith's Arcanum",
  "version": "1.0",
  "description": "A mystical toolbox for web artisans and code wizards",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "permissions": [
    "<all_urls>",
    "activeTab",
    "tabs",
    "storage",
    "downloads",
    "webRequest",
    "webRequestBlocking",
    "clipboardWrite",
    "notifications"
  ],
  "browser_action": {
    "default_icon": "icons/icon-48.png",
    "default_title": "WebSmith's Arcanum",
    "default_popup": "popup/popup.html"
  },
  "sidebar_action": {
    "default_icon": "icons/icon-48.png",
    "default_title": "WebSmith's Arcanum",
    "default_panel": "sidebar/sidebar.html"
  },
  "background": {
    "scripts": [
      "background/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_scripts/inspector.js",
        "content_scripts/measure.js",
        "content_scripts/responsive.js"
      ],
      "css": [
        "content_scripts/styles.css"
      ]
    }
  ],
  "web_accessible_resources": [
    "assets/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{6b3546c6-60cf-49af-9be7-30598b65986f}"
    }
  }
}