This is probably just an oversight like the "Gary Banner" typo, but I was looking through the creative inventory and I noticed that all mushroom blocks - red mushrooms, brown mushrooms, mushroom stems, mushroom cap blocks, and brown mushroom cap blocks are all mislabeled under just "Mushroom". I don't know if this has been posted before. If it has, then feel free to take this post down, I just wanted to let the people working on the game to know in case nobody told them. I included a 10-second video clip, sorry it wasn't a screenshot.
Thank you for your report!
However, this issue is Working as Intended.
The four mushroom items in creative inventory have always been called "Mushroom" in both Java Edition and Bedrock. This is by design. If you'd like to suggest a change, suggestions can be made at the Feedback site.
Incidentally, there's one other block like this: Both the whole melon and the melon slice are named simply "Melon".
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