Examine source code of Snapshot

{
  "description": "__MSG_extDescription__",
  "version": "4.0.3",
  "name": "__MSG_extName__",
  "author": "py-insights.com",
  "default_locale": "en",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_icon": "./images/snapshot-34.png",
    "default_title": "__MSG_defaultTitle__"
  },
  "icons": {
    "128": "./images/snapshot-128.png"
  },
  "manifest_version": 3,
  "permissions": [
    "history",
    "storage",
    "alarms"
  ],
  "optional_permissions": [
    "bookmarks",
    "cookies"
  ],
  "optional_host_permissions": [
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{596e8750-f4d7-4cb0-b3f1-4c9010e39b6c}"
    }
  },
  "externally_connectable": {
    "matches": [
      "*://*.instant.py-insights.com/*"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.instant.py-insights.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ]
}