In plain language
Modern consoles read the capability data at startup and build their video menu from it. Options that are not advertised do not appear — greyed out at best, absent at worst.
Why it matters in your setup
People conclude their television or console does not support a feature when in fact the capability never arrived. The usual culprits are an AV receiver in between, a soundbar in the video path, a television port that supports the mode on only some inputs, or a cable that cannot sustain the FRL rate.
Consoles also cache what they learned. After changing anything in the chain, a hot plug or a restart is often needed before the new capability set is picked up.
What the DR HDMI 8K does with it
Put a DR HDMI 8K between the console and the rest of the chain and you decide what the console is told. Twelve 4K120 EDID tables with different VRR, HDR and audio combinations mean you can present exactly the capability set you want, then use ISSUE HOTPLUG to make the console re-read it without unplugging anything.
Need the hardware?
Open the DR HDMI 8K product page on HDfury.uk.