what happens when 2 identical pictures are uploaded at rougly the same time?
in that case what would happen?
the firts gets removed or the last? is the lightest (File) conserved?
they keep the one with better tags or votes/favs?
is what i want to know
im not going to put my name by mistakeAgain

Whichever post is higher quality (larger resolution, less compression artifacts, etc.). If they're truly identical, the first one takes priority.

The one with better visual quality (both resolution and compression artifacts are a factor) stays. Filesize differences are incidental; creating an artificially smaller/larger file that's visually identical will not allow you to replace an older post. Otherwise, in the case of two truly identical images, older one usually stays.