The bug

In Bedrock Edition, the newly-added froglight blocks appear fully illuminated from angles. In Java Edition, this is not the case and certain faces appear darker than others, resulting in a parity issue.

The resource pack attached to this issue fixes this issue entirely for placed froglights and I give Mojang full permission to integrate these resources into vanilla Java Edition.

How to reproduce

This can be reproduced by placing down froglights in both Bedrock Edition and Java Edition, and checking to see if some sides are rendered darker than others.

Expected results

All six sides of the froglight block would be rendered at an equal brightness.

Actual results

This is true in Bedrock Edition, but not in Java Edition.

How to fix

Very easy - just define new versions of the "cube", and "cube_column_horizontal" template models which have the element set to ""shade": false,", and a new copy of "cube_column" which points to the new copy of "cube" that has shading disabled. The six froglight block models can now easily be repointed to these new models accordingly.

This is what I've done in the attached resource pack, so it's probably faster to just copy and paste these model files into the game to fix this rather than fixing it manually independently.