Vale Court Autofill is published by Vale and is covered by Vale's privacy policy: https://www.vale.legal/privacy-policy

What the add-on handles. When you start a fill from Vale, the add-on receives a one-time code from the Vale page and exchanges it with Vale for an access key that lasts at most one hour. It then reads that one matter's answers and its will and death certificate from Vale, and types them into the RedCrest form in your own session. The matter's details go only into the RedCrest page; the add-on sends them nowhere else.

What it sends to Vale: the one-time code and its verifier (to get the access key), a request to end the access when you finish, and, if RedCrest's form has changed, the ids of the form fields that differ (never their values).

What it stores: the access key and the marks it placed on the page, in the browser's session storage, which is cleared when the browser closes. It keeps no history and uses no analytics or tracking.