The widget is "pulldown menu with incremental search", and the question
is "did they allow multiple character search input" and, as a sub query
"how long after you hit a character does the hidden input field reset if
you don't hit enter".
Seems to me that Jeff Harrison coded a decent incremental search wrapped
around a browse lookup at one point ... or maybe it was Ron Klimasewski,
one of Microsys's other coders in the 90s. It's been a long time...
It's odd, when I have to do maintenance work on tables all three of us
had our fingers in, I can tell which of the three of us worked on a given
routine; we each had a different view of 1TBS. 
Cheers,
-- jra