Can anyone confirm a possible game bug?

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Can anyone confirm a possible game bug?
by on (#92405)
In Mega Man 5, after selecting a boss, there's the brief screen before the level loads of the boss where it's name is given. MMC3 IRQ's are used on this screen to scroll the top and bottom portions for a nice effect.

If you look closely on the bottom portion of that moving "bar", you'll see what appears to be an empty glossy circle. If you notice on Nestopia, slightly above that empty circle you can see very briefly, a sprite of a filled in circle flashes.

My question is, is that behavior expected? It would seem reasonable to assume that the filled in circle would fit over the empty one neatly. I also noticed an entry for Mega Man 5 on the Wiki, which only added to my confusion. :P