Is マイナポータル safe?

マイナポータル injects hidden DOM elements exposing extension version and app status to page scripts on matched government portal sites.

The extension's content script creates hidden input elements on Japanese government portal pages that expose its version number and native app installation status to any script running in the same page context. It also listens for CustomEvents from the page and forwards their raw payloads to a native messaging host (jp.go.cao.mpa) without schema validation or field allowlisting.