/usr/share/themes/Perl/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 7 8 9 10 | title_alignment=left
full_width_title=false
button_offset=0
button_spacing=2
active_border_color=#000000
inactive_border_color=#000000
active_text_color=#000000
inactive_text_color=#a2a0a2
|