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You can enter the name of the Icon in the Name attribute (Refer to the SLDS link) , refer to this link https://www.lightningdesignsystem.com/icons/
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Size
Adjust Icon sizes using the size attribute
There are five types of size
In the Size drop-down, select the size
XX-Small: You can set xx-smallsize on the icon
X -Small: You can set an x-small size on the icon
Small: You can set a small size on the icon
Medium: You can set medium size on the icon
Large: You can set the large size of the icon
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