This is an example hint.
This input will show an error if you select more than 2 items.
You can select a maximum of 2 items from the list.
This error is a bit contrived: ideally you would disable the selection of items when the user has selected the maximum allowed rather than showing an error, however it works for the purpose of demonstrating the component.
Number of items selected: {{selectedItems.length}}
Selected items: None