Examine source code of DataShield Media Blocker

{
  "manifest_version": 2,
  "name": "DataShield Media Blocker",
  "short_name": "DataShield",
  "description": "Prevents download of third party media files (Video,Images,CSS,JS,Fonts) reducing data usage and increasing load times.",
  "version": "1.5.2resigned1",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "storage",
    "contentSettings",
    "activeTab",
    "<all_urls>"
  ],
  "web_accessible_resources": [
    "BlockedByDataShield.png",
    "BlockedByDataShield.css",
    "BlockedByDataShield.js",
    "DataShield_Overlay.js"
  ],
  "background": {
    "scripts": [
      "DataShield.js"
    ]
  },
  "content_scripts": [
    {
      "js": [
        "DataShield_Overlay.js"
      ],
      "css": [
        "DataShield_Overlay.css"
      ],
      "all_frames": true,
      "run_at": "document_start",
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "icons": {
    "64": "icon_64.png",
    "128": "icon_128.png"
  },
  "browser_action": {
    "default_icon": "icon_128.png",
    "default_popup": "settings.html",
    "default_title": "DataShield Media Blocker"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{69dd9901-4d9d-4a56-b069-197e8813d374}"
    }
  }
}