What is De-spill?
When using a green screen with bright lights, it's likely that some of that green will reflect back onto the subject (you, the player). This will often appear as a green border around the edge of the subject, or a slight green tint over the whole subject. This green reflection onto the subject is called "spill". Spill is ugly, kills skin tones, and can make it very obvious you're on a green screen. It must be dealt with.
Spill can be suppressed with a technique called "de-spill". De-spill tries to replace the green spill with a more natural colour. The result is that green border is removed, and colours are more natural across the image.
How do I de-spill in LIV?
In your Camera Profile, go to the Keying tab and adjust De-spill Strength.
Set de-spill strength to 100% for maximum de-spill; or set to 0% to disable the effect.
Note: If you were previously using a LUT for the purpose of de-spill, you should consider disabling the LUT and using the in-built de-spill function in its place.