Sorry, just to clarify, when Linux 5.2 is the base for Libreelec, that's likely when the os will fully support 4k and HDR with the Pi4?
I'm curious so that I know for future reference. (I may consider a Pi4 then)
LE master branch is already on 5.3 and will bump to 5.4 soon .. but not for RPi4 which needs to remain on 4.19 until more V4L2 plumbing has been completed. Kodi is slowly inching towards HDR support. It's already possible to hack something up that works for some SoCs (not RPi4 yet) but we'd rather do it properly at a more measured pace. I'm not expecting to see "proper" HDR support for some time yet.