ConnectApi.ExtensionsCapabilityInput

Create or update extensions associated with a feed element.

Property	Type	Description	Required or Optional	Available Version
`itemsToAdd`	List<`ConnectApi.ExtensionInput`>	List of extensions to associate with the feed element.	Required for creating an extension Optional for updating an extension	40.0
`itemsToRemove`	List<String>	List of attachment IDs to remove from the feed element.	Optional for updating an extension Don’t specify for creating an extension	41.0

Apex Reference Guide