steps to reproduce

1. load the attached zul
2. type "aa" (a new item) quickly and press enter key before the popup shows up

current result

• the Chosenbox doesn't add the new item and doesn't highlight the "create new item" option, so pressing the enter key takes no effect.

workaround

see <script> in the attached zul

debug info

• in _doEnterPressed(), when pressing an enter before the popup shows, it will show the popup without selecting (highlighting) any item. So pressing enter with no selected item doesn't create any new item.
• In JIRA issue Labels field, you need to wait for a popup open after typing an unexisting item to create a new item. But there is another design, that pressing enter key creates a new item immediately, please refer to https://select2.github.io/examples.html#tags