I wanted to apply a modifier between two cones. Here is what you can see before I make it visible:
As you can see, the bigger cone just disapeared. I tried to update the normals (Shift-N in edit mode or Mesh > Normal > Recalculate outside) of both the small and the large cone, still the same issue. Actually, the cone disappear even if I use union!
Also, to make sure that the pointy vertex is not removed, I made sure to shift a bit the smaller cone:
Here is the file: http://www.filedropper.com/01problememodifier
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