/etc/quotatab is in quota 4.03-2+deb9u1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | # This is an example quotatab file
#
# This file is used as a translation for device names, so a warnquota message
# makes sense to the user.
#
# syntax is as follows:
#
# colon ':' is used to specify the start of the substituted text
# pipe '|' is used to specify a line break
#
# device:substituted text
# device:text on line 1|test on line2
#
# For instance if you would like to have warnquota tell the user their
# 'mailspool' is full instead of '/dev/hdb1' is full, use the following
# example.
#
# /dev/hdb1:mailspool
|