Adding text box as an option

[gotters]

I am trying to add a text box as one of the options because I am using the multiselect as a filtering element on a separate list. I want the text box to act as a free text filter.
I have tried many things but cant get this to work...

I tried enabledHTML and inserted the input box in the option however the textbox shows but is disabled (i cant enter any text)

I tried using the enableFiltering textbox and tried to prevent the filtering of the options but I cant seem to do that.

Can anyone advise how to do this?

[davidstutz]

Related: #668, #602.