events, mouse button 2 possible bug?

[Steven J Abner]

 Hello, I am new to xlib/xcb and started off (not knowing any better) 
with gdk/gtk3.
So created the event loop but in the handling of events I came upon an 
oddity. I wrote xcb, no response, so assume this is a bug because of 
response.
 The event sequence for button 2 mouse press:
window 83886080, LEAVE_NOTIFY (623,112)
window 83886080, ENTER_NOTIFY (623,112)
window 83886080, BUTTON_PRESS Button 2 modifier 0 (623,112)
 An assumption would be if this is in fact a feature of button 2, that 
it is to signal a drag begin event. But that seemed a little illogical 
to me. I would think that to be something like:
window 83886080, BUTTON_PRESS Button 2 modifier 0 (623,112)
window 83886080, LEAVE_NOTIFY (623,112)
window 83886080, ENTER_NOTIFY (623,112)
or BUTTON_PRESS, FOCUS_OUT, FOCUS_IN.
 If is a feature, can someone please (as simplistically as possible) 
explain how to use. If not a feature, what is best way to block/ignore 
so as not to run extra code that may be attached to handling event 
LEAVE_NOTIFY of a button press event.
 Steve