Examine source code of FocusBarrier

{
  "manifest_version": 2,
  "name": "FocusBarrier",
  "version": "1.0.0",
  "description": "FocusBarrier - rebranded extension",
  "icons": {
    "48": "icon.png",
    "96": "icon.png",
    "128": "icon.png"
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/icon48.png"
    },
    "default_popup": "popup.html",
    "default_title": "CleanBrowse"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "storage",
    "tabs",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      },
      "id": "{33bb1525-5e69-441e-8744-886d62c01207}"
    }
  },
  "action": {
    "default_popup": "popup.html"
  }
}