Changes in 2019.1.3? Skybox environment reflections missing

Maybe this is a known issue, or a known change?

I haven't found a more recent report than some posts in 2015, but I just tested a transition from 2018.4 to 2019.1.3 and all my shiny standard shader skybox reflections disappeared. Sort of. A simple scene with nothing but the default blue/tan skybox and a reflective standard shader on a capsule went from looking like Terminator 2 to looking like Tron 1.

In 2018.4, I mocked up this super quick basic scene. This is a super-simple Standard shader in the normal rendering pipeline. Note the prefab preview icon, the scene camera and the game view all agree that this simple primitive reflects the blue sky.



I then saved this scene, and switched to 2019.1.3. The saved scene looked identical. But if I created a new scene or entered the Prefab mode to look at the chrome object, this is what I see. Also note that all the preview icons have also lost their environment mapping appearance.



I did notice that across the update, the Quality settings shifted all build platforms down to the lowest quality level. But returning to the Ultra quality did not seem to have any effect. Although there were a lot of differences in the .unity files between a scene that works and a scene that doesn't, it was not clear to me what change would impact the environment mapping this way.

 

Replying to myself. Maybe the eagle-eyed reader will spot the difference... the "Auto Generate" option now defaults to OFF, and apparently is also OFF in the Prefab mode stage scene. Even though there's not a lot to generate with the built-in skybox, clicking "Generate Lighting" or turning on the automatic generation will bring back the basic skybox reflection.

 

Thanks! It's now mid-2023, and this was useful to me (old Unity 2019 project). Not sure why I didn't come across this issue before, if it was changed in newer versions to update automatically. I've played quite a bit with Lighting settings and still had no clue what was going on.