[Bug] preview of prefab in editor causes warning spam if not set up for lightmapping

Unity Engine
1

I’ve got a mesh with no normals on the root of a prefab. Selcting the prefab asset causes Unity to spam this:

Mesh does not have normals for Global Illumination. Please ensure there are normals in your modelling package, or set the Normals property to Calculate on the Asset.
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

We’re using a custom lighting setup where we’re not using normals for some models, so it’s correct for the model to not have normals. We’re not using Global Illumination either.

Do I have to report a bug, or is this straight-forward enough that you’ll be able to fix it?

Unity 2018.4. This error spam is so bad that it becomes near impossible to drag the prefab into the scene due to the amount of warning messages generated (several hundred per editor frame). It’s also generated with the preview tab not open.

2

We (Unity) will need a bug report. It probably won’t land in Prefab Team, it sounds like an editor or graphics issue, but we’ll figure that out internally. In general it’s very rare that anybody here reads a forum post and then immediately drops everything they were working on to fix it right that instant, so we generally always need bug reports to have a place to track issues so they don’t get lost.