Lighting window allows non-cube map texture for Environment Reflections, throwing invalid texture type (2D) error

Thank you for reporting a bug to Unity. After reviewing the behavior, we've confirmed it aligns with the current design and intended use of the feature. We understand this may differ from your expectations or workflow. We believe that input validation should happen at consumption, not in the picker. There are several reasons for this: 1) Even if we did validation in the picker it would not be perfect: The user can still pick a "correct" texture, then mutate the texture settings afterwards and end up in a "wrong" state. This severely limits the value of validating in the picker as we cannot prevent "bad state" anyway. 2) The user may actually _want_ to change it to an invalid texture in a situation where they intend to mutate the texture settings after assigning it (manually or via script). If we validate in the picker we block this behavior. 3) I was not able to find any existing places where we do this type of special filtering in the picker. By special I mean filtering/validation based on importer settings (as opposed to filtering on object type which is fine). 4) Validating at consumption (instead of input/picking) is how we do it in other places of Unity, e.g. custom textures in Reflection Probes. Combined, it seems that we should prefer to do validation where the settings are consumed -- not where they are set. We will close this case as 'As Designed.' If you have feedback on how the feature could better meet your needs, please let us know - we value your input and consider it in future improvements.

With the release of Unity 6.3, 6.2 is no longer supported.