Mushrooms generate on bedrock ceiling of the nether

Did you place any blocks on the nether ceiling? if so, this allows entities to spawn as well as mushrooms when you generate new terrain.

Yes I did to test if the lc value bug still exists. But flying further revealed more mushrooms generating in chunks where the lc value has not been raised.

Edit: Th lc value from the screenshot is not from the block I placed but from the mushrooms that generated.

I tested it, and can confirm.