Just a flash and it's gone -- startup

(I said I was going to post this, I have hesitated because I can't be
definitive)

Since i don't know what it is, I can hardly describe it except to ask if
other's have seen this or if it may be indicative of a problem -- or know
how to capture the last part of the desktop startup phase.

Problem Statement (finally)

When I start or reboot, things go normally, and the desktop appears in (last
I checked) 56 seconds.

Right after the Screen is completely populated (less than a second) there is
a box that appears for maybe a 1/10 *or less* of a second (not long enough
to read) in the center.

Performance does not appear to be affected. I am familiar with the
occasional boxes for "configuration" or "settings" update. This ain't one
of those. All running processes in Taskmon are identifiable, nothing
unusual showing in TASKINFO2003 processes either. Nothing recent or strange
in the 4 or so places for startup either.

This flash occurrence is recent. My paranoia says "invisible toolbar".

I guess my main question is if there is any way to capture that last phase
of startup or to slow down the start-up process about a hundred-fold so that
I could see it.

FACE