Examine source code of Claude Usage Meter

{
  "manifest_version": 3,
  "name": "Claude Usage Meter",
  "version": "1.3.4",
  "description": "Real time Claude usage tracker. See your session, weekly and Fable limits, reset times, just above the Claude.ai chatbox.",
  "browser_specific_settings": {
    "gecko": {
      "id": "claude-usage-meter@selectorshub.com",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage",
    "alarms",
    "notifications",
    "cookies",
    "tabs"
  ],
  "host_permissions": [
    "https://claude.ai/*"
  ],
  "background": {
    "scripts": [
      "browser-compat.js",
      "background.js"
    ]
  },
  "action": {
    "default_popup": "popup/popup.html",
    "default_title": "Claude Usage Meter",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://claude.ai/*"
      ],
      "js": [
        "browser-compat.js",
        "content-script.js"
      ],
      "css": [
        "overlay.css"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "https://claude.ai/*"
      ],
      "js": [
        "page-injector.js"
      ],
      "run_at": "document_start",
      "world": "MAIN"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "icons/icon16.png",
        "icons/icon48.png",
        "icons/icon128.png"
      ],
      "matches": [
        "https://claude.ai/*"
      ]
    }
  ]
}