application10 -- does scrolling work reliable for you?

[Stefan Salewski <mail ssalewski de>]

gtk+-3.18.1/examples/application10

cd aplication10
glib-compile-schemas .
glib-compile-resources exampleapp.gresource.xml --target=resources.c --generate-source
gcc -o main main.c resources.c exampleapp.c exampleappwin.c exampleappprefs.c `pkg-config --libs --cflags 
gtk+-3.0`

./main exampleapp.c

Make word list visible and window size medium size, so that not all text
is visible.

Now click on button "gtkbuilder"

It was my feeling that the text area with this search term should scroll
into visible area. Often that works, and search term is selected. But it
works not always for me. Sometimes just nothing happens.

OK, after some more testing: When I click on another button and then on 
 "gtkbuilder" again, that word scrolls into visible area. So the problem
is: When word is selected already, but moved outside visible area, then
searching for exactly that term does not work or at least does not
scroll it into visible area? Why may that occur? And what is the fix,
something like un-selecting all before starting search?