Examine source code of Imagedelete

{
  "description": "Image Block",
  "manifest_version": 2,
  "name": "ImageBlock",
  "version": "5.0",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "32": "icons/1.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c032597d-6f1b-4a1a-b087-c6da7263ff06}"
    }
  }
}