Examine source code of Adjust Viewport Size

{
  "manifest_version": 2,
  "name": "Adjust Viewport Size",
  "version": "1.0.1resigned1",
  "author": "FullStackChoreman",
  "description": "Resize window adjusts to viewport. ブラウザの表示部分に合わせてウインドウの大きさを変更できます。",
  "icons": {
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "64": "icons/icon64.png",
    "96": "icons/icon96.png"
  },
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "browser_style": true,
    "default_icon": {
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "64": "icons/icon64.png",
      "96": "icons/icon96.png"
    },
    "default_title": "Adjust Viewport Size",
    "default_popup": "popup.html"
  },
  "options_ui": {
    "page": "options.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "fxaddon@adjustviewportsize",
      "strict_min_version": "57.0"
    }
  },
  "background": {
    "scripts": [
      "common.js",
      "background.js"
    ]
  },
  "commands": {
    "adjust-shortcut-1": {
      "suggested_key": {
        "default": "Alt+Shift+1"
      }
    },
    "adjust-shortcut-2": {
      "suggested_key": {
        "default": "Alt+Shift+2"
      }
    },
    "adjust-shortcut-3": {
      "suggested_key": {
        "default": "Alt+Shift+3"
      }
    },
    "adjust-shortcut-4": {
      "suggested_key": {
        "default": "Alt+Shift+4"
      }
    },
    "adjust-shortcut-5": {
      "suggested_key": {
        "default": "Alt+Shift+5"
      }
    },
    "adjust-shortcut-6": {
      "suggested_key": {
        "default": "Alt+Shift+6"
      }
    },
    "adjust-shortcut-7": {
      "suggested_key": {
        "default": "Alt+Shift+7"
      }
    },
    "adjust-shortcut-8": {
      "suggested_key": {
        "default": "Alt+Shift+8"
      }
    },
    "adjust-shortcut-9": {
      "suggested_key": {
        "default": "Alt+Shift+9"
      }
    }
  }
}