Mushroom stems aren't registered in commands

Mushroom stems aren't placable by setblock or fill commands or give commands

 

How to replicate:

1.type/give @p or /setblock ~~~

2. Then type mushroom_stem(that is the identifier of the block)

Expected:

"Mushroom_stem" will appear in the list of givable/ placable things

What happened:

 "Mushroom_stem" won't appear in the list, therefore, the command will not work

 

Using addons, you can make a feature rule and you can make it add a tree or plant feature that places this block. The identifier for it is "minecraft:mushroom_stem"

I tried it and the mushroom stem block spawned like how I wanted it to.