You can check if this fix is installed using the following script condition:
if eval FileExists "UIO\Public\ySIColorfulIconsFix.txt"

Additionally you can check for this io() interface trait in the following menus:
> HUDMainMenu, InventoryMenu, MapMenu, StatsMenu, RepairMenu, ItemModMenu
if eval GetUIFloatAlt "HUDMainMenu\_ySIColorFulIconsFix" == 1

If you want to integrate this fix natively in your interface XML you can add something like this:
<systemcolor>
<copy> 0 <copy>
<add>
<copy src="io()" trait="systemcolor"/>
<onlyifnot> <copy src="io()" trait="_ySIColorFulIconsFix"/> <eq> 1 </eq> </onlyifnot>
</add>
</systemcolor>

Remove the interface color from any ySI JSON icon template by adding the following component
"systemcolor": -1

NOTE: The expected syntax for is currently bugged and doesn't remove interface color properly.
"systemcolor": 0