Examine source code of Dynamic Zoom

{
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "browser_style": true,
    "default_icon": "icons/app-48.png",
    "default_popup": "options/page.html",
    "default_title": "Dynamic Zoom Options"
  },
  "commands": {
    "toggle-dynamic-zoom": {
      "description": "Toggle Extension",
      "suggested_key": {
        "default": "Ctrl+Shift+0"
      }
    },
    "decrease-dynamic-zoom": {
      "description": "Decrease the simulated width",
      "suggested_key": {
        "default": "Ctrl+Shift+8"
      }
    },
    "increase-dynamic-zoom": {
      "description": "Increase the simulated width",
      "suggested_key": {
        "default": "Ctrl+Shift+9"
      }
    }
  },
  "content_scripts": [
    {
      "js": [
        "content.js"
      ],
      "matches": [
        "*://*/*"
      ]
    }
  ],
  "description": "Dynamically adjusts the zoom based on the width of the window.",
  "homepage_url": "https://github.com/ingolemo/firefox-dynamic-zoom",
  "icons": {
    "48": "icons/app-48.png"
  },
  "manifest_version": 2,
  "name": "Dynamic Zoom",
  "permissions": [
    "storage"
  ],
  "version": "2.3",
  "options_ui": {
    "page": "options/page.html",
    "browser_style": true
  },
  "applications": {
    "gecko": {
      "id": "{4b6e6274-681a-45a4-98db-7c7d03df3560}"
    }
  }
}