Narrower

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Narrower",
  "description": "Add margins to wide pages.",
  "version": "1.0",
  "author": "Andrey Leshenko",
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "browser_action": {
    "default_icon": {
      "19": "images/popup_icon19.png",
      "38": "images/popup_icon38.png"
    },
    "default_popup": "popup.html"
  },
  "permissions": [
    "activeTab"
  ],
  "background": {
    "page": "empty.html"
  }
}