Edit the first item (Apple) and remove the e, then press enter. "Appl" should be added, but it's not.

It seems currentText is not changed in onAccepted if it is a substring of the previously selected text.

The workaround is simple. Simply change find(currentText) to find(editText) in the following example:

   if (editableCombo.find(currentText) === -1) {
         choices.append({text: editText})
         currentIndex = editableCombo.find(editText)
   }