undeclared identifier 'UIGammaToLinear'

[Niaxor]

Shader error in 'UI/RoundedCorners/RoundedCorners': undeclared identifier 'UIGammaToLinear' After import -
I'm assuming this is a minimum Unity version requirement that I'm not meeting, I'm currently using Unity 2019.4.

According to this forum post - Re similar issues in TMP https://discussions.unity.com/t/3-2-0-pre-6-undeclared-identifier-uigammatolinear/931099/8
This in-built shader function requires at minimum Unity 2021.3.34f1 or later.

Just logging in-case I'm wrong, or if you wanted to add a Minimum Unity Version to the readme, if there's a particular version in released that I should be aware of that doesn't require this function please let me know :)