what is this weird viewport shading? Part of this mesh is now shaded in the viewport in solid mode with this look that changes shade when you rotate the view. Like a hologram.
What is it?
Blender... where you hit the wrong key combo and 2 hours later have no idea what obscure hidden feature you've enabled.
It was this setting under object data parameters. &quot;Normals-&gt;auto smooth&quot; Which is somehow different from the other ways of doing it.