Examine source code of Simple Print

{
  "name": "Simple Print",
  "version": "1.3resigned1",
  "manifest_version": 2,
  "description": "Convert web articles into printable PDFs",
  "homepage_url": "https://pdf.fivefilters.org/simple-print/",
  "browser_action": {
    "default_title": "Simple Print",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "activeTab"
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+Shift+P"
      }
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a3ba5c84-c1e6-4e1e-9951-529285b37633}"
    }
  }
}