Another FIND oddity

All of a sudden, the "ctrl-F" find box is sucking in highlighted text from
my member. Did not used to do this.

In order to limit the search (and/or replace) to a section of code, I
select that code and press ctrl-F. You should see what happens when
several pages of code are selected!

I sort of liked the prior ctrl-F action of "sit there and do nothing till I
type something in the box". I cannot locate a preference to control it.
Is there one?

Stu