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You can change icons by using their category
The Icon component comes in five categories
In the Category drop-down, select the category
Action: Action icons are for use with quick actions on touch-screen devices
Custom: A custom icon is for icons that have Custom icons are for use with a very specific or unique action.
Doctype: Doctype icons represent document file formats:
Standard: Custom Object Standard icons represent the entities and objectserrors, warnings, information, and question mark
Utility: Utility icons are simple symbols in a single color that identify labels and actions across many form factors
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Using the Fill color you can apply solid color to the excess space of an image
e.g. The Icon is displayed in red if you enter that color
Fill color: Red
