Thumbnails for child blueprint are not updated after changing a component in child blueprint

Thumbnails for child blueprint are not updated after changing a component in child blueprint

1. Create blueprint A with component static mesh X
2. Set X as any static mesh
3. Create blueprint B as A’s child
4. Change X in B to another static mesh

RESULT:
Thumbnail for B in content browser won’t change after changing static mesh, the same happens for components like skeletal mesh and probably the others that can change thumbnail icon

Thumbnails Not Showing Properly on Child BPs

Thumbnails Not Showing Properly on Child BPs

[4.7.5] Derived Asset Thumbnails