Warning: this is an htmlized version!
The original is across this link,
and the conversion rules are here.
# -*- coding: raw-text-unix -*-

# (find-fline "/etc/X11/fvwm2/system.fvwm2rc" "Buttons on the title bar")
#
Mouse 0 6 A Maximize 1024p 768p
Mouse 0 8 A Maximize 800p 600p

# (find-fline "/etc/X11/fvwm2/system.fvwm2rc" "AddToDecor default-decor")
#
AddToDecor default-decor
+ ButtonStyle Reset
+ ButtonStyle 2 Vector 16 20x20@1 30x20@1 50x40@1 70x20@1 80x20@1 80x30@0 60x50@0 80x80@0 70x80@0 50x60@0 30x80@0 20x80@0 20x70@0 40x50@1 20x30@0 20x20@1
+ ButtonStyle 4 Vector 2 50x80@1 50x20@1
+ ButtonStyle 6 Vector 5 25x25@1 25x75@1 75x75@0 75x25@0 25x25@1
+ ButtonStyle 8 Vector 5 25x25@1 25x75@1 75x75@0 75x25@0 25x25@1



# fvwmrc-to-2 1.7a
# Output to /home/root/.fvwm2rc
# Warning: StickyForeColor not in fvwm2, omitted
# Warning: StickyBackColor not in fvwm2, omitted
# Warning: Unknown keyword ClickToFocus passed through
# Note: Conversion of old ButtonStyle; values rounded
# Note: Conversion of old ButtonStyle; values rounded
# Note: Setting mouse bindings to sticky menus
# Note: GoodStuff renamed to FvwmButtons

DeskTopSize 5x4