Examine source code of Fill Screen Anywhere — Zoom Into Videos

{
  "manifest_version": 3,
  "name": "Fill Screen Anywhere",
  "version": "1.6",
  "author": "Farid Zelli",
  "homepage_url": "https://github.com/FaridZelli/FillScreenAnywhere",
  "description": "Zoom into videos on almost any website.",
  "icons": {
    "16": "fillscreenanywhere.svg",
    "32": "fillscreenanywhere.svg"
  },
  "permissions": [
    "storage"
  ],
  "action": {
    "default_popup": "/popup.html",
    "default_icon": {
      "16": "fillscreenanywhere.svg",
      "32": "fillscreenanywhere.svg"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "FillScreenAnywhere@FaridZelli",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {}
  },
  "options_ui": {
    "page": "/popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "commands": {
    "fill-screen": {
      "suggested_key": {
        "default": "Ctrl+Alt+F"
      },
      "description": "Fill Screen"
    },
    "remove-letterbox": {
      "suggested_key": {
        "default": "Ctrl+Alt+L"
      },
      "description": "Remove Letterboxing"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle",
      "all_frames": true
    }
  ]
}