--- Comment #2 from Heiko Tietze <[hidden email]> ---
You screenshot shows the font name rendered as the font looks. This dropdown
will not modify any other property like size or color. The full preview is
limited to the left hand paragraph style dropdown or the styles list at the
sidebar. If you define a character style with a certain font name, -size, and
-color it will be shown full WYSIWYG there.
If you expect to get immediate feedback when the selection changes this issue
is kind of duplicate of bug 112175.