How to check what files have been customised in /etc?

[Colin Law]

On Sun, 13 Dec 2020 at 16:18, Ralf Mardorf via ubuntu-users
<ubuntu-users at lists.ubuntu.com> wrote:
>
> On Sun, 13 Dec 2020 11:44:33 +0000, Colin Law mentioned drop-in
> directories/files.
>
> Those drop-in files are tricky, especially when using a rolling
> release, but they could cause the same kind of issues for release model
> distros, probably when upgrading to the next release or when using
> third party repositories.
>
> A famous example is /etc/security/limits.conf.
>
> You set all your limits in one place by /etc/security/limits.conf, in
> my domain e.g. especially "rtprio" and "memlock". Then a
> packager/vendor decides to override those settings by a drop-in file.

I have never ever had a problem with other overrides overriding mine.
It probably depends what sort of system one is setting up.

Colin