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Apart from the "Cut Content" lines below it is worth not removing any of the existing lines, although alterations (such as new icons) can be made. This is because internally applied effects and item properties still use hardcoded references to this 2da file.
The line IDs for Poison (20) and Disease (21) hardcode the changed colour bars (brown and green respectively); these are lines are recommended not to change but are also good for making custom poison and diseases look proper.
However unused cut content / lines can now be changed quite drastically with EffectIcon.
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