/etc/mozpluggerrc.d/20-header.conf is in mozplugger 1.14.5-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | # DO NOT EDIT THIS FILE
# It is automatically generated by update-mozpluggerrc using templates
# from /etc/mozpluggerrc.d. Changes will be lost on upgrade.
#
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