How unfortunate. Validating may be expensive, but you only need to do it when preparing to show the mesh, not all the time.

Thanks, the python command did let me see the mesh.

I should have mentioned that the last version of Blender I used before 2.92 was 2.82, and didn't seem to have this issue. Strangely, it seems very specific to "Leather Pants M", since "Leather Pants F" works fine.

Thanks, but the info for Mac just says that a crash reporter appears and I have to copy the text from that. However, no crash reporter appears. Blender just immediately disappears with no messages of any kind.

How do I find the crash log?

Updated repro steps:
Open the file. You will be in weight paint/polygon selection mode.
Click one of the buttons on the jacket that are in the green area of the weights.

Ok, I can post in the requests. I always get the feeling that they aren't looked at though.
Question on this topic... what is the expected behavior if the tool panel is showing for a vertex group operation, then you select a different vertex group and make changes to the still-showing tool panel?

The panel could still operate exactly as it does, with realtime feedback, but the ability to dismiss the panel when finished would be the expected design. I've never seen any other software behave the way that tool panel does, where it just sits there forever after you're done, potentially allowing for further accidental changes. As suggested, selecting a different vertex group should make it go away too, especially if selecting a vertex makes it go away already. Consistency is good.

Please re-open this ticket as originally reported, with my additional explanation of the unintuitive nature of the tool.

It's unintuitive because it's very unclear how the tool panel works.
Here's how it currently works (if it worked properly)...

1. Select a vertex group.
2. Choose the "Levels" menu item.
3. Set the desired values in the tool panel.
4. There is no confirmation button, or any other clear way to dismiss the tool panel after you've set the values you want.
5. Choose another vertex group.
6. Set the values in the tool panel. What? It affects the previously selected vertex group instead?

6a. To make it work, you have to again select the "Levels" menu item after selecting the next vertex group, although there is NO DIFFERENCE in how it appears on the screen. No indication of what vertex group the panel is affecting.

But like you said, the base color has no effect in Blender when there is a texture connected. So, effectively, the base color is pure white when a texture is connected. It should export this way to match how Blender treats it.

I agree that most of this is just bad UI/UX decisions instead of a bug, but I would still argue that exporting with that "unused in Blender" color instead of white is a bug, since it's not shown or expected. It's exporting differently than represented. That seems like a bug to me.

I think the real problem is that the Base Color picker disappears when a texture is connected. It should still be pickable in that situation.
Plus, I would love the default color to be pure white. Who uses slightly less than pure white as the normal base color??

I guess it's possible that I was working with Un-Subdivide-friendly meshes before, but it seems very odd that I would have so much success with it then suddenly no success.

All I know is that it worked before I upgraded to 2.81.

Link to video of me doing the above steps: https://www.youtube.com/watch?v=5PS2HefA9ww

Uploaded blend file.

1. Created plane.
2. Pressed tab to go to edit mode on plane.
3. Right-click, click Subdivide.
4. Increased "Number of Cuts" to 10.
5. Pressed Command-T to convert all quads to triangles.
6. Pressed tab to exit edit mode.
7. Switched to wireframe mode to see polygons.
8. Added "Decimate" modifier.
9. Switched Decimate mode to Un-Subdivide.
10. Increased "Iteration" and saw no difference.

Thanks for all the responses... eventually it became clear. I'm hoping that this could be addressed in the UI by simply adding the extra dropdown instead of the object picker.

Upon further thought, I think I know what you mean by "X around Y", etc...
This makes me think that the UI should have two dropdowns instead of the need to make an object and transform it.
"Bend [X/Y/Z] axis around the [X/Y/Z] axis."

This is overly complicated. There shouldn't be a need for a second factor. Only a single axis should be necessary to do what someone wants:

• Choosing X with 360 degrees of bend should form a circle around the X axis.
• Choosing Y with 360 degrees of bend should form a circle around the Y axis.
• Choosing Z with 360 degrees of bend should form a circle around the Z axis.

I'm sorry, but this is not clear nor intuitive at all. Why wouldn't it just work around the chosen axis without the need for another object? After all, the modifier is named "simple deform", not "complicated deform". :)

Yes, I could and I have. The screenshots and description explain how to create the problem. Do I need to attach the actual blend file with it already set up?

I'm not sure I understand what you mean by only being one choice. It gives the options of X, Y, and Z.

That's strange. I've never had to do that before, so I didn't even know the UV Map node was a requirement. Thanks for the info.

I'm not sure what you mean by plug in compared to how it's already set up. The UV map for Lemon has the correct geometry. The material on that same geometry is using the Lemon texture.

Also, I have noticed that UV unwrapping does not work on the lemons anymore, if I try to experiment with making a new UV map.

Attached zip file with the blend and two textures.

It's been "experimental" (AKA broken) for a very long time now.

Where do I find the "Front Faces Only" and "2D Falloff" options in the UI???

Ohhhhhhhh, the "Tool" tab of the "N" panel is where everything is that I couldn't find.

Update: I just figured out how to "show tool settings". With that shown, I could see that the paint brush was in "Subtract" mode for some crazy reason. I wish all of those brush settings appeared on the right click tool menu.