It takes lot of time for rending thousands of records from client side, some times browse gets crashed, causes performance issue. Virtualization support will help us to overcome this issue, as the same provided in Angular 1.x and Kendo MVC controls. Can you please provide virtualization support for Autocomplete & Multi Select controls.
The normal DropDown with its feautures would allow do multiselect its items or if the standard Multiselect would allow to avoid the linebreaks. A possible solution would be to add only one label with the text of the selected Items and an ellipsis when there get selected too many items to show all text, then you show the text hole text in the tooltip. https://github.com/telerik/kendo-angular2/issues/160
The dropdowns should provide an easy way to have certain items in the list as inactive. The easiest way could be an attribute. In addition to [textField] and [valueField] an [inactiveField] could be added. If the assigned data field is a boolean the item in the list can be either enabled or disabled. Reason for this request is, that those value lists often are dynamic, meaning that an item in the list could be superseded by a new one. But the existing records in the database still could reference the older item, but new records should be prevented from selecting the new item.
The floating label for drop down in angular as in material.io.