Black surface in Meshmixer I was working on a model today and I need to make the black surface into a normal surface so that the ship's cockpit is solid. I am unable to select the black surface. I tried using the flip normals feature, but I was still unable to select it. Any advice on how to make it into a solid is greatly appreciated. Thanks. :)

Edit: Here's the link to the file
https://drive.google.com/file/d/1mbTdeeZqhNJx-WlXNqF8mD8QYDSI3Vh_/view?usp=sharing
With the model file available, I was able to use Edit, Generate Face Groups. This allows one to continue with Select, {set small cursor}, select reversed panels, Edit, Flip Normals.

The above steps resolve the cockpit windows, but meshmixer's Analysis, Inspector shows a sea-urchin-presentation of other flaws, including what appears to be zero thickness walls in some locations.