Why is it needed?
For example: In this screenshot, my text is not visible, but I don't want to either the background colour or the text colour of this scene.

To make my text visible, I can change the shadow to it.

To change the Text Shadow:
Go the section 'Captions'.
Captions>Caption Colours>Text Shadow>Select the appropriate shadow

For my text to be visible, I am selecting dark.

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