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You can change icons by using their category
The icon 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: Custom Object icons represent the entities and objects
Doctype: Doctype icons represent document file formats:
Standard: Custom Object icons represent the entities and objects
Utility: Utility icons are simple symbols in a single color that identify labels and actions across many form factors
Name
You can enter the name of the Icon in the Name attribute (Refer to the SLDS link)
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You can enter a color in the Fill Color attribute (By using the Fill color you can customize the Icon color)
e.g. The Icon is displayed in red if you enter that color
Fill color: Red
