Bug Realtime GI: Light mode is currently overridden to Realtime mode, but only in Build?

Hello everybody,

our current small project uses Unity 2022.2.16 with the built-in render pipeline and we became interested in using Global Illumination recently. First, we enabled both Baked GI and Realtime GI, but then decided to go with only Realtime GI enabled. The problem we came across was that our scene had much more indirect lighting in the built player (Windows) than in the editor. After hours of trial and error, we figured that in the editor it lacked the indirect lighting of the sun (Directional Light), whereas said indirect lighting was present in the build. This happened always, even after generating lighting manually.

However, there was a false assumption, given by the following warning message on the sun light:

Light mode is currently overridden to Realtime mode. Enable Baked Global Illumination to use Mixed or Baked light modes.

On the verge of giving up, I got curious and changed its light mode from Mixed to Realtime, and voila, the issue was gone! Now both the build and the editor contained the indirect lighting for the sun and therefore looked identical.

So is this a bug? Shouldn't they look identical anyway, even if the directional light was set to Mixed in this scenario?

Thanks in advance!