/usr/share/themes/Stoneage/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 | active_text_color=#ffffff
button_offset=1
button_spacing=2
full_width_title=true
maximized_offset=3
show_app_icon=true
title_horizontal_offset=2
title_shadow_active=frame
title_vertical_offset_active=0
title_vertical_offset_inactive=0
|