How to `dump(MakieCore.Transformable)`

I’m searching a way to access MakieCore.Transformable.

I was reading docstring of Makie.rotate!() and found out that there is a type called Transformable.

help?> Makie.rotate!
  rotate!(Accum, scene::Transformable, axis_rot...)

  Apply a relative rotation to the Scene, by multiplying by the current rotation.

  ─────────────────────────────────────────────────────

  rotate!(t::Transformable, axis_rot::Quaternion)
  rotate!(t::Transformable, axis_rot::AbstractFloat)
  rotate!(t::Transformable, axis_rot...)

  Apply an absolute rotation to the Scene. Rotations are all internally converted to Quaternions.

apropos() told me that it’s under MakieCore.

julia> apropos("Transformable")
MakieCore.Transformable
Makie.translate!
Makie.rotate!
Makie.scale!

But I can’t use help on it.

help?> MakieCore.Transformable
ERROR: UndefVarError: MakieCore not defined
Stacktrace:
 [1] top-level scope
   @ ~/julia-1.7.2/share/julia/stdlib/v1.7/REPL/src/docview.jl:538

julia> import MakieCore
 │ Package MakieCore not found, but a package named MakieCore is available from a registry. 
 │ Install package?
 │   (@v1.7) pkg> add MakieCore 
 └ (y/n) [y]: 

I’m sure this will install the obsoleted version of MakieCore.

How can I access, @less, subtypes(), or read docstrings of MakieCore.Transformable? For now all I can do is clone the repo and read the source.

It seems that Makie.Transformable is the one?

julia> Makie.Transformable
MakieCore.Transformable

help?> Makie.Transformable
  abstract type Transformable

  This is a bit of a weird name, but all scenes and plots
  are transformable, so that's what they all have in common.
  This might be better expressed as traits.

julia> subtypes(Makie.Transformation)
Type[]

julia> dump(Makie.Transformation)
Transformation <: MakieCore.Transformable
  parent::Base.RefValue{Transformation}
  translation::Observable{Vec{3, Float32}}
  scale::Observable{Vec{3, Float32}}
  rotation::Observable{Quaternionf}
  model::Observable{StaticArrays.SMatrix{4, 4, Float32, 16}}
  transform_func::Observable{Any}

Somehow auto-completion doesn’t work on this.

julia> Makie.T<TAB>
              
TEXTURE_RESOLUTION TextureAtlas        Top
Text               Theme               TopLeft
TextBuffer         TimeSeries          TopRight
Textbox            Toggle              Transformation

Is this known condition?