/usr/share/themes/Wallis/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 | button_offset=2
button_spacing=1
full_width_title=true
maximized_offset=4
show_app_icon=true
title_horizontal_offset=3
title_shadow_active=under
title_shadow_inactive=false
title_vertical_offset_active=1
title_vertical_offset_inactive=1
|