schauma

``` OS: Ubuntu Core 20 (ubuntu:GNOME/ubuntu) Word size of FreeCAD: 64-bit Version: 0.21.2.33771 (Git) Snap 908 Build type: Release Branch: tag: 0.21.2 Hash: b9bfa5c5507506e4515816414cd27f4851d00489 Python 3.8.10, Qt 5.15.7, Coin 4.0.0,...

I cannot give you a definitive answer. This file has been opened and modified in 3 different FreeCAD versions so my suspicion would be that maybe something got mixed up...

@sheetmetalman Thank you for all your insightful research. I have to admit that most of what you are describing is way above my head, but I am very thankful that...