Trac #1479
All our typeaheads use this, but I made it an option that must be enabled
explicitly since it is not default bootstrap behavior.
(imported from commit 97852dc407d1f6dbe46b5fdd2c56d3ed8c6718d2)
The option caused some race conditions on Firefox, and it is
really made moot by the naturalSearch option anyway.
(imported from commit dc7080c905ced9b2f4ad4275d82549acf09a59f7)