Trello Card Numbers

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "__MSG_appName__",
  "version": "0.0.10",
  "manifest_version": 2,
  "description": "__MSG_appDescription__",
  "icons": {
    "16": "images/icon-16.png",
    "128": "images/icon-128.png"
  },
  "default_locale": "en",
  "background": {
    "scripts": [
      "scripts/background.js"
    ]
  },
  "page_action": {
    "default_icon": {
      "19": "images/icon-19.png",
      "38": "images/icon-38.png"
    },
    "default_title": "Trello Card Numbers"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*.trello.com/*",
        "https://*.trello.com/*"
      ],
      "js": [
        "scripts/content.js"
      ],
      "run_at": "document_end",
      "all_frames": false
    }
  ]
}