Badge Arcade will always overwrite anything GYTB makes, and vice versa, although either can also be recovered easily. If you injected custom badges through a different method, GYTB will always delete them, but Badge Arcade seems to sometimes let them stay and sometimes not. In any case, if you back up your extdata, there's not much to worry about.Just wondering, do you know if nintendo badge arcade really rewrites all of your badges data deleting the badges you had? That makes me feel a bit afraid of testing this, since i already injected a lot of custom badges and i can still get new ones in the app...
Ah. Seems there must be more to getting the button to appear than just the extdata existing. I need to look into this...That option isn't shown on 9.2 home menu though. (I have a current 3ds with badge arcade so I know how it works)