In my map, I have a circle stacked under a slider (1/2) apart. When I try to copy and paste this to another location in the song, this happens-



Testing the map or leaving the editor seems to correct this problem, but it's still pretty pesky.

Oh yeah this, it's been around as long as osu! has.

Unfortunately this isn't such an easy one to fix, due to the way objects are cloned internally.
*marks as "for a rainy day"*

Edit:.....

This probably has been occurring more frequently since the slider update. all sorts of weird things occur when you paste sliders.