Cloud mode
Remove the extension from your browser's extensions page. Your account and rules stay on the server — if you reinstall later, everything is still there. To delete your account and data, sign out from the extension and contact us via email.
Local mode
Remove the extension, then run this in Terminal to remove the local helper:
bash ~/.local/share/autopilot/uninstall.sh
This keeps your saved rules by default. Add --purge to remove them too.
Sorry to see you go. Mind sharing why?