Hello,
Editing SGraphNode as you suggest might have unintended consequences - it is the base class for all nodes in Unreal Engine.
UMaterialExpressionCustom manually reconstructs it’s SGraphNode, see “UMaterialExpressionCustom::PostEditChangeProperty(…)” from MaterialExpressions.cpp.
If you can make a test project that shows this crash, we can try investigating this code path to find what is happening.
The guide for test projects: [Content removed]