Examine source code of Netflix Keyboard Blocker

{
  "manifest_version": 2,
  "name": "Block Netflix Keyboard Interactions",
  "version": "1.0",
  "description": "Prevents Netflix from interacting with your keyboard.",
  "icons": {
    "48": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.netflix.com/*"
      ],
      "js": [
        "block.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{acab7aa4-56e3-4cc2-99ea-4bf3ccf4d707}"
    }
  }
}