Within the source in AddTokenAsync the case is handled that the AutoSuggestBox is not the last item.

But the UI does not to allow that case.

To make the TokenizingTextBox fit for all thinkable usecases:

• declare an Interface for the Tokens, such as IToken
• in that have a CanBeAutoSuggestBox getter
• have a method in the TokenizingTextBox to activate the conversion from displaying an Item implementing the IToken interface and CanBeAutoSuggestBox is true to the current AutoSuggestBox. Such as ActivateAutoSuggestBoxForItem(IToken item)
• the programmer can then implement a TemplateChooser (if not possibe to use one yet, has to implemented too) which shows items which CanBeAutoSuggestBox as a TextBlock without being inside a buton
• clicking on such an item the programmer can call the ActivateAutoSuggestBoxForItem form within the ItemClick event handler to have edit that content. The programmers implementation can leave the result of such edits as an TextBlock or convert it into a Token by setting CanBeAutoSuggestBox to false.
• from the end users perspective the TokenizingTextBox contains text and Tokens seamingly.
• also nice would be drag and drop of items - either to rearrange them or to drop them from or into other places
• it should be possible to have drop event handlers to make it possible to drop on Item onto another. Such as the end user wanting to combine two tokens together
• if that it implemented Copy & Paste of items should be also possible. The API should make it possible to combine an Item with one in a clipboard by clicking onto the target item which presents a flyout menu which such option...