HDR UI monitor in linux

Sorry if this sounds too basic, but, what exactly should I expect from the new “HDR UI” setting?

I mean, I have a PD2725U monitor, with HDR support. Connecting this monitor to windows systems, by simply enabling the HDR option on windows settings, the monitor detects it and switches automatically. My mate has a mac pro and everything works similar. But… What about Linux? As far as I know, linux does not support HDR at the operating system level. Back to flame, I have tried to enable this feature and set up a project for testing. But the monitor doesn’t detect anything. It still in sdr mode. The change in the UI is visible, but what else? Should I be able to see hdr on the UI monitor?