Adding to a growing list of new features to be released in the 3.5 update, a new temperature color option has been added. It lets you set the blue to yellow light range of the screen.
Other additions coming in the 3.5 update include a saturation slider, HDR support for external displays, additional display upscaling options (including Nvidia Image Scaling), improved SMT handling (no more needing to turn SMT off for emulators), updated kernel, and more stuff that I’m probably forgetting.
HDR is basically unsupported on desktop Linux, though a lot of work has been done recently. Valve meanwhile decided to do their own userspace implementation for their UI and supporting HDR in Proton.