Sources.list modified?

Hi all,

I've noticed that my sources.list has been modified.

For example:
http://deb.debian.org/debian-security buster/updates InRelease

was removed. I don't know if this happened during the last pihole update.

I'm running pihole on a raspberry pi 4. Has anyone experienced the same problem?

I only have this two sources:
http://raspbian.raspberrypi.org/raspbian buster InRelease [15.0 kB]
http://archive.raspberrypi.org/debian buster InRelease

Pi-hole doesnt touch the Apt sources.list file.
If your running PiOS, there shouldnt be any Debian repositories configured:

pi@ph5b:~ $ sudo grep -v '^\s*#\|^\s*$' -R /etc/apt/sources.list*
/etc/apt/sources.list:deb http://raspbian.raspberrypi.org/raspbian/ buster main contrib non-free rpi
/etc/apt/sources.list.d/raspi.list:deb http://archive.raspberrypi.org/debian/ buster main

Pi-hole doesn't have the ability to do that.