Steps to reproduce:
1. Open the “user’s attached project”
2. Open the “Assets/Scenes/Tractor Whiteboxing Scene” Scene
3. In the Hierarchy window, select the “Terrain/trees(2)/tree 5” GameObject
4. In the Inspector window, press the Kebab Menu of the “Optimized Leaf Material (Material Variant)” Material Component
5. Press “Remove Unused Properties…”
6. Observe the crash

Reproducible with versions: 6000.0.32f1, 6000.1.0a9
Couldn’t test with versions: 2021.3.47f1, 2022.3.55f1 (The Menu doesn’t have “Remove Unused Properties…” item)

Reproducible on: macOS 15.1 (M1 Max)
Not reproducible on: Windows 11

First few lines of StackTrace:

#0 0x00000103137308 in Material::RemoveUnusedProperties()
#1 0x0000046ed901c8 in (wrapper managed-to-native) UnityEngine.Material:RemoveUnusedProperties_Injected (intptr) [\{0x449c97710} + 0x60] (0x46ed90168 0x46ed9021c) [0x157ec2a80 - Unity Child Domain]
#2 0x0000046ed900e0 in UnityEngine.Material:RemoveUnusedProperties () [\{0x132d458a8} + 0x70] (0x46ed90070 0x46ed900f4) [0x157ec2a80 - Unity Child Domain]
#3 0x0000046ed8fa88 in UnityEditor.MaterialEditor:RemoveUnusedProperties (UnityEditor.MenuCommand) [\{0x34f786510} + 0x70] [/Users/bokken/build/output/unity/unity/Editor/Mono/Inspector/MaterialEditor.cs :: 3117u] (0x46ed8fa18 0x46ed8fa9c) [0x157ec2a80 - Unity Child Domain]
#4 0x0000035aa65ea0 in (wrapper runtime-invoke) <Module>:runtime_invoke_void_object (object,intptr,intptr,intptr) [\{0x152d6bf68} + 0x70] (0x35aa65e30 0x35aa65f3c) [0x157ec2a80 - Unity Child Domain]