How much RAM on RPi 4 for LibreELEC to play 4K HDR, 2GB or 4GB?

I'm upgrading from a Pi 3 to a Pi 4 (I need the Pi 3 for something else, and I hope the 4 will eventually support 4K HDR) but I don't know which version of the Pi 4 to get.

Is the 2GB RAM version good enough for LibreELEC and eventually playing 4K HDR content once LE can, or do I need the 4GB version (which costs 50% more here)? I've read that timeshift on live TV can use the extra RAM, but I never watch live TV so that's not a factor.

Quote from chewitt

Also worth pointing out that 4K HDR is 90% functional already; 4K@60 still needs work (but there is not much media in that refresh rate) and 10-bit/12-bit are still WIP, but 8-bit output is more than watchable.

Good to know, and thanks for all the hard work!