find . \( -name '*.h' -o -name '*.c' \) -exec sed -i 'N;/^\n$/D;P;D;' {} \;

Shadow and padding was never part of theme. This format was created by
mutter, and it is an incompatible change.

This adds 'invisible_border' to metacity theme. This invisible
border will be used for resize cursor area.

Add app-menu button support in themes. This is done only to support
metacity theme format 3.5 version. Marco will not show this
button!

Based on metacity commit:
https://gitlab.gnome.org/GNOME/metacity/commit/6a2cc159

Add an additional color type to pick up colors defined with
@define-color in the GTK+ theme's CSS:

  gtk:custom(name,fallback)

(where "name" refers to the name defined in GTK+'s CSS, and fallback
refers to an alternative color spec which is used when the color
referenced by "name" is not found)

The main intent of the change is to allow designers to improve
Adwaita's dark theme variant without having to compromise on colors
which work in the light variant as well.

https://bugzilla.gnome.org/show_bug.cgi?id=648709

NOTE: Patch copied from mutter and adapted for metacity.

With the existing background functions, single buttons can not be
styled separately - on the left side, the style of the left button
is picked, and the right button's style on the right side.

As theme authors may want to add rounded corners to button groups
as a whole, it makes sense to treat the case of a single button in
a group differently.

https://bugzilla.gnome.org/show_bug.cgi?id=635683

NOTE: Patch copied from mutter and adapted for metacity.