Examine source code of SessionSwap

{
  "manifest_version": 2,
  "name": "SessionSwap",
  "version": "3.0.5",
  "description": "Save and switch cookie + localStorage profiles per website",
  "permissions": [
    "cookies",
    "storage",
    "tabs",
    "activeTab",
    "<all_urls>",
    "proxy",
    "browsingData",
    "webRequest",
    "webRequestBlocking",
    "privacy"
  ],
  "commands": {
    "profile-prev": {
      "suggested_key": {
        "default": "Ctrl+Up"
      },
      "description": "Switch to previous profile"
    },
    "profile-next": {
      "suggested_key": {
        "default": "Ctrl+Down"
      },
      "description": "Switch to next profile"
    }
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon16.png",
      "32": "icon32.png",
      "48": "icon48.png",
      "128": "icon128.png"
    }
  },
  "background": {
    "scripts": [
      "shared.js",
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start",
      "all_frames": true,
      "match_about_blank": true
    }
  ],
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "cookie-profile-switcher@kingextension",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}