Mutter has some code for translating the GSettings settings from
org.gnome.desktop.peripherals.* schemas to the corresponding libinput
settings:
https://git.gnome.org/browse/mutter/tree/src/backends/meta-input-settings.c
https://git.gnome.org/browse/mutter/tree/src/backends/x11/meta-input-settings-x11.c
There is no replacement in gnome-flashback for this.
I.e. if you enable tap-to-click via gsettings, it will get ignored,
while it should be translated to 'libinput Tapping Enabled' libinput
property.
Can we please have that mutter code integrated into gnome-flashback?