Opaque objects between camera and material break refraction

I’m not sure if this a bug but when placing a static mesh with an opaque material in front of a translucent material with a refraction enabled, the silohuette of the mesh disables the refraction effect.

Below, I created a simple example. The first image shows just the refraction material, working as intended. However, when the sphere is placed in front of it, there’s an area around the mesh that isn’t affected by the refraction.

I’ve disabled ‘separate translucency’, played around with ‘transparency sort order’ and tried about everything I know. Can anyone help?

Thanks