We recently ran into a crash in ScriptCore.cpp:2135 on version 4.12.5 while updating a character’s animation blueprint. The problem seems to be that Stack.MostRecentProperty is not null, but Stack.MostRecentPropertyAddress is null. We get this crash immediately after the following exception:
LogScript:Warning: Attempted to access missing property. If this is a packaged/cooked build, are you attempting to use an editor-only property?
I looked at where that exception was being thrown (ScriptCore.cpp:1320) and it looks like if VarProperty is not null, but !IsA((UClass*)VarProperty->GetOuter()) is still true, Stack.MostRecentProperty can be non-null while Stack.MostRecentPropertyAddress is still null.