[Milhouse]

Is it true we need to wait for official Linux 5.1 or 5.2 for true HDR support?

I forget what I read, but it sounded like many things need to be fixed in Linux before libre elec can truly support the pi4 properly?

5.3 for HDR with Intel/AMD (although the full stack - mesa, ffmpeg, drivers, kodi etc. - will need tweaking). And when I say "Intel" I generally mean only their latest hardware, ie. Gemini Lake/Ice Lake.

For RPi4, the HDR support needs to be added and there's currently not yet a time frame for that as other more basic and essential (ie. Raspbian-type) issues are being addressed first by the Raspberry Pi Foundation developers.

The idea is to move ARM devices supported by Kodi - that is all RPi devices, including RPi4, plus Allwinner, Rockchip, Amlogic, NXP/iMX, Qualcomm etc. etc. - to a common GBM/V4L2 vendor-neutral software platform for Kodi 19, which should make HDR easier to support across the board. Once progress is made towards GBM/V4L2 then you'll start seeing RPi4 builds in this thread, but until then the best option is the official LibreELEC 9.2 RPi4 builds (based on GBM/MMAL and Kodi 18.3).