Same here in UE 5.0.3, but, for me, it only happens sometimes, not every time I load the project.
I already tried to disable Live-Coding, but it keeps happening.
My case is a bit different though because the class that loses it’s cpp parent is inside a custom plugin I’m writing (and is a UUserWidget).
I’ve also tried to create a new project and import the plugin, but the result is the same: 2/3 of the times the editor crashes at 75% of the startup.