I think you could use HUD conditions for this. Have an image of an unchecked box and one with a checked box, and then use the condition to check if completed or not.
The HUD Quest Task List component has options to limit which tasks to display, e.g. using one list to show the finished tasks and one for the others. That way you can use separate prefabs with different setups to display finished and unfinished tasks.
Or, in menu screens and quest dialogues, the quest layouts can use separate texts for the task states, e.g. adding an icon to the text that way.
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Or, in menu screens and quest dialogues, the quest layouts can use separate texts for the task states, e.g. adding an icon to the text that way.
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