Hi @sflege,
Nope: at this time, typeaheads support only a single value. You can of course add more than one typeahead parameter...but that often gets messy quickly.
If you have a relatively short and static list of items in mind (e.g. users), another Old School option is to use a multi-select list box parameter and set up the entries showing the Name of each user as written, but the Value of each user as their ID. By doing so, in addition to then having a "multi", you can also do some interesting filters such as "contains $$USER.ID", which hits the value, and therefore returns only those items to which their user has been (multi) selected.
Regards,
Doug
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