Editing nested prefabs sometimes leaks objects into the currently open scene.

Hi

We're having a problem where as I mentioned, editing nested prefabs sometimes leaks objects into the currently open scene. I'm not exactly sure how to reproduce it but it goes something like this... if I select a prefab within the scene, open it and then select a nested prefab and open that and do some edits, when I back out to the scene level there are sometimes copies of the nested prefab in the scene. Sometimes these go unnoticed and things break

Is anyone else having this problem? I've tried to reproduce it in a simple project to submit a but report without any luck so far.

I'm currently using 2018.3.0b9 and the problem is present, upgrading to b10 breaks something in our project so I haven't been able to test in newer beta's.

Any help is greatly appreciated. Thanks for reading

 

Please make sure to submit a bug-report for this issue as well, if you didn't do that already and it still reproduces with b12.
https://unity3d.com/unity/beta/guide-to-beta-testing#tab-3

 

Thanks @SteenLund good to know