Selection To Cursor / Parenting Armature Glitch

Mik Model.blend (2.76 MB)

Hi all.
In the following file, the selected group of vertices vanish whenever I either send them to the 3D cursor, or if ever I parent the armature to the model. The same thing happens whenever I add new vertices into the object, they just disappear as well under the same circumstances. This seemed to be happening ever since I added a track bone to the model’s left eye, so I’m hoping somebody with more knowledge on this may be able to shed some light here.

Note: I’m trying to copy/paste the iris from the left eye onto the right eye, where the 3D cursor currently is. So ideally, the solution should allow me to do that.

Thank you for reading, and I look forward to hearing from you.

Solved it myself.

I simply added the vertices and all after removing the tracking constraints, to any who may face that issue later on.

If any stumble upon this forum and know the actual explanation behind why this happened, feel free to leave it.

When you are in edit mode, with vertex select, and you shift s to cursor, you are telling each vertex to go to the cursor. If you want the whole area to stay the same use the selection to cursor with offset. If you make your vertex size say 10 pixels you will see them at the cursor. You just have a small vertex that is hard to see. I think that is what you are looking at, but I’m not sure.