Whenever an action with the Color data type is created - SetColor for instance - it does not have any default color data set. This means you can end up with a SetColor action that looks like it’s set to white, but is actually set to nothing.
The gameplay effect of this is that firing the SetColor action might set the color to an invalid value, or (usually) simply solid black, instead of the white color that the UI shows.
This is also an issue in the I/O Debugging menu.
Steps to Reproduce
Create a SetColor (or similar) action in I/O.
Press “Copy All Outputs”.
Paste the text into Notepad.
It will have the Color DataType field but no Data field.
This causes it to set the color to an incorrect value when fired.
Notes / Media
Example 1: I/O SetColor action not having Color data set. The UI shows white but there’s not actually a color set.

and so, the cube turns solid black instead.
Example 2: I/O Debugging menu having unset Color data. The UI shows white but the cube turns black.
Once you’ve actually clicked the color picker and chosen a color, the Data field will be there and it’ll work as expected, but it adds a minimum of 2 extra clicks per SetColor action just to ensure that it works as expected, which kinda sucks.