Multiple selection in combobox
possibility to select multiple entries in combobox.
(e.g. by pressing "Ctrl"-key and clicking the entries) #15842
Not exactly answer to this request, but Version 7 will feature new form element – List Control – which alows multiselction – #27117
Kim Beck commented
It would be nice to have a multi selection list, where users can tick off members, instead of having to hold down CTRL. Similar to how it works in Microsoft Reporting Services: