A number of things that gnome-settings-daemon monitors for all the GTK+ applications aren't currently available for GTK+ Wayland clients, only through XSettings.
As we already monitor fontconfig configurations, enabled GTK+ modules and whether applications should use animations, export those through a D-Bus interface.
Based on patch by Martin Blanchard
522640a6 xsettings: Expose monitored settings through D-Bus
plugins/xsettings/gsd-xsettings-manager.c | 136 +++++++++++++++++++++++++++++-
1 file changed, 134 insertions(+), 2 deletions(-)