Noticing this behaviour across numerous systems and roms that have the same releases on different systems - roms from other systems are showing up in libraries (i.e. dreamcast games showing in playstation or gameboy) with the paths for the directories to said roms - causes a bit of a nightmare for loading them as the emulators are expecting the current system format and it seems to load the top rom in the path list.
This is on latest release (2.0.54)