systemd-delta — Find overridden configuration files
systemd-delta [OPTIONS...]  [SUFFIX...] 
systemd-delta may be used to
                identify and compare configuration files in
                /etc that override default
                counterparts in /usr. The command
                line argument can be one or more name of a subdirectories of
                /etc or
                /usr/lib to compare, such as
                tmpfiles.d, sysctl.d or
                systemd/system.
When no argument is specified a number of well-known subdirectories are searched for overridden files.
The following options are understood:
-h, --help¶Prints a short help text and exits.
--version¶Prints a short version string and exits.
--no-pager¶Do not pipe output into a pager.
-t, --type=¶When listing the differences, only list those that are asked for. The list itself is a comma-separated list of desired difference types.
Recognized types are:
--diff=¶When showing modified
                                files, when a file is overridden show a
                                diff as well. This option takes a
                                boolean argument. If omitted it defaults
                                to true.