Ok this is not a 100% bug, more like a necessary feature for those who have epilepsy but i think there should be something like biome blend for the nether atmosphere because if you are flying with elytra and change fast between atmospheres, it can be a bit weird. This is a gif of just moving back and forth between atmospheres
Thank you for your report!
However, this issue is a Duplicate of MC-170879.
That ticket has already been resolved as Invalid, which means this is not considered a bug but a feature request. Please do not leave a comment on the linked ticket.
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