Hi John,
This code is ran during the PiHole install with DietPi for 404:
#Generate index page that replaces adverts
cat << _EOF_ > /var/www/index.html
<html>
Blocked by Pi-hole.
<script>window.close();</script>
</html>
_EOF_
window.close should automatically close any popups.
by installing with the curl method
The v133 update stopped this working so I have switched to the DietPi fork and this is working fine
Bizarre, was this from v132 to v133 or an earlier version? The v132 patch code has no effect on PiHole (from what I can see)