strange behavior of emacs during search

[bostjanv]

Hi,
I'm not sure whether the problem I'm describing is specific to emacs on
Windows, or to emacs in general. Therefore, I will be sending this mail
to both forums.

I cannot explain the following behavior of emacs:

I'm using emacs on a laptop (Lenovo P71) running Windows 10. When I'm
using an external monitor, the search proceeds as expected (C-s takes
you to the next occurrence); however when I'm using the internal monitor,
things are different: one or two C-s's take you, as expected, to the
next occurrence; but the following C-s displays the Edit menu in a special
way: when one clicks on the Edit option on the menu line, the Edit menu
is displayed without the title; this time it is displayed with the title
"Edit" in boldface. Since this behavior detracts from the task at hand,
I would like to get rid of it.

Regards,
bostjanv