/usr/share/themes/Agua/xfwm4/themerc is in xfwm4-themes 4.10.0-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | full_width_title=false
title_alignment=center
button_spacing=2
button_offset=2
active_text_color=#000000
inactive_text_color=#7b8eaa
|