Screen space reflections do not work for orthographic camera. This is unfortunate because our application uses orthographic camera as a default. We need SSR in order to improve the client render quality. Please see here for BJS repo.
You can see that the other meshes are reflected off the purple plane when the camera is perspective mode. But no reflections are shown when camera is orthographic.
I don’t know exactly if it’s a bug or intended : SSR is a Post-Processed layer which acts directly on the render using Normal Map and Depth Map. Both of them are subject to be hugely estimated or even missing in orthographic mode, because of the “no perspective” way of projecting the scene.
That said, SSR in orthographic rendering is theorically possible. I let official BJS Devs answer whether or not it’s a bug or it’s a known unimplemented feature