fpgen.yml mapped the drawn window.pageYOffset (e.g. 528) to
screen.pageYOffset, and the browser returns that value from scrollY on
every read, so a page saw one scroll position forever whatever the user
did. Real scroll offsets are live page state, not part of a device's
fingerprint, so neither offset is mapped any more.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
