An example of refraction effects in a sphere, created in Unity 2019.4. Made to accompany a tutorial I wrote.
As usual with Unity projects you'll need to do a little ritual after downloading. When you first open the project it'll take a few minutes to build the local library. You'll then need to Open Scene to open the actual sample scene in the project (Unity silently generates a default start scene and shows you that instead.) To be safe you may need to restart Unity too.