Examine source code of YouTube Auto WPM Speed

{
  "manifest_version": 3,
  "name": "YouTube Auto WPM Speed",
  "version": "1.0.0",
  "description": "Auto speed controller based on WPM.",
  "permissions": [
    "storage",
    "webRequest"
  ],
  "host_permissions": [
    "*://*.youtube.com/*",
    "*://*.googlevideo.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "youtube-wpm-auto-speed@git.dep.ovh",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "action": {
    "default_popup": "popup.html"
  },
  "commands": {
    "toggle-global-mode": {
      "suggested_key": {
        "default": "Alt+G"
      },
      "description": "Toggle Global Mode"
    },
    "toggle-auto-mode": {
      "suggested_key": {
        "default": "Alt+A"
      },
      "description": "Toggle Auto/Manual Mode"
    },
    "increase-max-speed": {
      "suggested_key": {
        "default": "Alt+Up"
      },
      "description": "Speed +0.2x"
    },
    "decrease-max-speed": {
      "suggested_key": {
        "default": "Alt+Down"
      },
      "description": "Speed -0.2x"
    },
    "increase-target-wpm": {
      "suggested_key": {
        "default": "Alt+Period"
      },
      "description": "Target WPM +10"
    },
    "decrease-target-wpm": {
      "suggested_key": {
        "default": "Alt+Comma"
      },
      "description": "Target WPM -10"
    }
  }
}