|CommentIcon||An icon which allows the user to add comment text to a block.|
|IconType||Defines the type of an icon, so that it can be retrieved from block.getIcon|
An icon that allows the user to change the shape of the block.
For example, it could be used to add additional fields or inputs to the block.
An icon that warns the user that something is wrong with their block.
For example, this could be used to warn them about incorrect field values, or incorrect placement of the block (putting it somewhere it doesn't belong).
|Icon||The abstract icon class. Icons are visual elements that live in the top-start corner of the block. Usually they provide more "meta" information about a block (such as warnings or comments) as opposed to fields, which provide "actual" information, related to how a block functions.|