Add-to-scene option does not work when importing numbered files

I maybe have found a small bug in OVITO.

When you have three different files with names similar to y1.xyz, y2.xyz and y3.xyz and you want to "add to scene" then they are not added - ovito adds only the first file. however, when i rename the files to yone.xyz, ytwo.xyz and ythree.xyz then I can "add to scene" without any problem.