endflash causes the endstone under the islands to turn green

The 25w33a changelog says

When they [end flashes] happen skylight intensity increases flooding the dimension with purple light

There are a couple of ways to read this: either the sky light becomes purple, and thus the dimension is mostly flooded with purple light (so the green shadowed areas are intended), or the skylight intensity is supposed to increase in such a way that the entire dimension, including shadowed areas (but excluding areas lit by blocks; see MC-301024), becomes purple (so this is a bug). I think the former interpretation is more likely correct, but since I’m not certain I will confirm this so Mojang can see it.

Thank you for your report!
After consideration, the issue is being closed as Working as Intended.

Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.

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