Examine source code of Add to Couch

{
  "manifest_version": 3,
  "name": "__MSG_extensionName__",
  "version": "1.0.0",
  "description": "__MSG_extensionDescription__",
  "default_locale": "en",
  "short_name": "Couch",
  "homepage_url": "https://couchreader.app",
  "author": "Alexander Johmann",
  "browser_specific_settings": {
    "gecko": {
      "id": "{9a321786-5402-4dc1-afb1-081fed7cd1b8}",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png",
    "256": "icons/icon256.png",
    "512": "icons/icon512.png"
  },
  "action": {
    "default_title": "__MSG_actionTitle__",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png",
      "256": "icons/icon256.png",
      "512": "icons/icon512.png"
    }
  },
  "permissions": [
    "activeTab",
    "tabs",
    "storage",
    "nativeMessaging",
    "contextMenus",
    "theme",
    "notifications"
  ],
  "background": {
    "scripts": [
      "accent-colors.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://*/web/extension-bridge*"
      ],
      "js": [
        "bridge-content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "host_permissions": [
    "https://*/*"
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self';"
  },
  "options_ui": {
    "page": "options.html"
  },
  "commands": {
    "save": {
      "suggested_key": {
        "default": "Ctrl+Shift+S",
        "mac": "MacCtrl+Command+S"
      },
      "description": "__MSG_saveCommandDescription__"
    }
  }
}