After the upgrade to Devuan chimaera (Debian Bullseye), I received a message Authentication Required to Create Managed Color Device when trying to log in remotely (via VNC).
A little research and I found the excellent articles at https://c-nergy.be (see links at bottom), where they (Griffon) walks through how they found the problem, researched the hell out of it, and found a long term solution. Here is a summary, but I recommend you read the two posts at the bottom.
Note: Their article was written for Ubuntu, but works just fine for Devuan (and, I assume, Debian)
edit /etc/polkit-1/localauthority/50-local.d/45-allow-colord.pkla
[Allow Colord all Users] Identity=unix-user:* Action=org.freedesktop.color-manager.create-device;org.freedesktop.color-manager.create-profile;org.freedesktop.color-manager.delete-device;org.freedesktop.color-manager.delete-profile;org.freedesktop.color-manager.modify-device;org.freedesktop.color-manager.modify-profile ResultAny=no ResultInactive=no ResultActive=yes
Note: the Action line is over 270 characters long. That is correct.