Examine source code of D-Scramble

{
  "name": "D-Scramble",
  "description": "Scamble your images, let them be seen only by people you decide.",
  "version": "0.2",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "src/jsbarcode128.js",
      "src/barcode_reader.js",
      "src/algo3_6.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "detect_images.js"
      ]
    }
  ],
  "permissions": [
    "storage",
    "contextMenus",
    "tabs"
  ],
  "browser_action": {
    "default_icon": {
      "16": "images/icon16.png",
      "32": "images/icon32.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    },
    "default_title": "D-Scamble",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1d54a0a4-3856-44ab-b09d-9c593c2e51a6}"
    }
  }
}