Wayland: Night Light doesn't work with Proprietary Nvidia drivers

$ mutter --version
mutter 3.30.0

$  gnome-shell --version
GNOME Shell 3.30.0

$ lsb_release -a
No LSB modules are available.
Distributor ID:	Debian
Description:	Debian GNU/Linux unstable (sid)
Release:	unstable
Codename:	sid


$ apt-cache policy nvidia-driver
nvidia-driver:
  Installed: 390.77-1
  Candidate: 390.77-1

I am excited to be among the first end users to be trying out GNOME Wayland with proprietary NVIDIA drivers, but I found that Night Light doesn't change the hue of the display very much (if at all?). In X11, it is a dramatic shift to a deep yellow colour, but on Wayland I don't think I see a change at all. This must be related to the NVIDIA driver, since on X11 the Night Light effect was interrupted when I opened nvidia-settings.

My monitor is reported as an Aculab Ltd 27" - the actual model is "Shimian" - a Korean reseller of rejected LG panels. The display was purchased in 2013, and the resolution is 2560x1440.

Let me know if there's any further information you require, or if I can be of further assistance in testing.