You might wanna consider the file system access api on chromiums https://googlechromelabs.github.io/text-editor/ https://googlechromelabs.github.io/text-editor/

You might wanna consider the file system access api on chromiums https://googlechromelabs.github.io/text-editor/ https://googlechromelabs.github.io/text-editor/ There is both a public and a private filesystem mode.