At the moment, it's not currently possible to add a custom color type field, similar to the Color field on Projects. It has been requested that we add Color as a new field Type option, so that a Color field can be added to custom entities to track the color of certain items.
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Please make the "color" field field type a first class field type. The field type is currently used by SG but unavaliable for customization. The "color field type is actively being used on the Task, Step, Status, Project, Phase, and Department entity. This is one of a few outstanding requested field type which should be promoted to first class field types. Other second rate field types that would be useful for customization include "entity_type" and "uuid".
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