We set a cookie so that nobody sees an Ethnio screener twice on the same domain for 30 days. You can turn this on or off under screeners >> publish for any given screener:
The main issue with this is that if you are visiting a site to test the screener, you need to clear all ethnio cookies to see the screener. This will not affect new visitors, but as the account owner, just be aware of this when you test out your screener. You'll have three ethnio cookies that normal visitors won't have, just from seeing the screener on different pages or being logged into ethnio.
Pro Tip: Just search for "ethn" in the cookie-clearing part of your browser and delete ethnio_displayed to be ale to see the screener again for testing.