CategoricalVector not defined

Julia Version 1.6.0
Commit f9720dc2eb (2021-03-24 12:55 UTC)
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-11.0.1 (ORCJIT, skylake)
Environment:
  JULIA_EDITOR = code
  JULIA_NUM_THREADS = 6
  JULIA_PKG_DEVDIR = c:/git/

When I try to use the package I get this error

[ Info: Precompiling GLFixedEffectModels [bafb0ae5-e5f5-5100-81b6-6a55d777c812]
ERROR: LoadError: LoadError: LoadError: UndefVarError: CategoricalVector not defined
Stacktrace:
  [1] top-level scope
    @ ~\.julia\packages\GLFixedEffectModels\ylcQT\src\vcov\vcovcluster.jl:21
  [2] include(mod::Module, _path::String)
    @ Base .\Base.jl:386
  [3] include(x::String)
    @ GLFixedEffectModels.Vcov ~\.julia\packages\GLFixedEffectModels\ylcQT\src\vcov\Vcov.jl:1
  [4] top-level scope
    @ ~\.julia\packages\GLFixedEffectModels\ylcQT\src\vcov\Vcov.jl:25
  [5] include(mod::Module, _path::String)
    @ Base .\Base.jl:386
  [6] include(x::String)
    @ GLFixedEffectModels ~\.julia\packages\GLFixedEffectModels\ylcQT\src\GLFixedEffectModels.jl:2
  [7] top-level scope
    @ ~\.julia\packages\GLFixedEffectModels\ylcQT\src\GLFixedEffectModels.jl:51
  [8] include
    @ .\Base.jl:386 [inlined]
  [9] include_package_for_output(pkg::Base.PkgId, input::String, depot_path::Vector{String}, dl_load_path::Vector{String}, load_path::Vector{String}, concrete_deps::Vector{Pair{Base.PkgId, UInt64}}, source::Nothing)
    @ Base .\loading.jl:1213
 [10] top-level scope
    @ none:1
 [11] eval
    @ .\boot.jl:360 [inlined]
 [12] eval(x::Expr)
    @ Base.MainInclude .\client.jl:446
 [13] top-level scope
    @ none:1
in expression starting at C:\Users\RTX2080\.julia\packages\GLFixedEffectModels\ylcQT\src\vcov\vcovcluster.jl:21
in expression starting at C:\Users\RTX2080\.julia\packages\GLFixedEffectModels\ylcQT\src\vcov\Vcov.jl:1
in expression starting at C:\Users\RTX2080\.julia\packages\GLFixedEffectModels\ylcQT\src\GLFixedEffectModels.jl:2
ERROR: Failed to precompile GLFixedEffectModels [bafb0ae5-e5f5-5100-81b6-6a55d777c812] to C:\Users\RTX2080\.julia\compiled\v1.6\GLFixedEffectModels\jl_8429.tmp.
Stacktrace:
  [1] error(s::String)
    @ Base .\error.jl:33
  [2] compilecache(pkg::Base.PkgId, path::String, internal_stderr::Base.TTY, internal_stdout::Base.TTY)
    @ Base .\loading.jl:1360
  [3] compilecache(pkg::Base.PkgId, path::String)
    @ Base .\loading.jl:1306
  [4] _require(pkg::Base.PkgId)
    @ Base .\loading.jl:1021
  [5] require(uuidkey::Base.PkgId)
    @ Base .\loading.jl:914
  [6] require(into::Module, mod::Symbol)
    @ Base .\loading.jl:901
  [7] eval
    @ .\boot.jl:360 [inlined]
  [8] eval
    @ .\Base.jl:39 [inlined]
  [9] repleval(m::Module, code::Expr, #unused#::String)
    @ VSCodeServer ~\.vscode\extensions\julialang.language-julia-1.1.38\scripts\packages\VSCodeServer\src\repl.jl:124
 [10] (::VSCodeServer.var"#47#49"{Module, Expr, REPL.LineEditREPL, REPL.LineEdit.Prompt})()
    @ VSCodeServer ~\.vscode\extensions\julialang.language-julia-1.1.38\scripts\packages\VSCodeServer\src\repl.jl:99
 [11] with_logstate(f::Function, logstate::Any)
    @ Base.CoreLogging .\logging.jl:491
 [12] with_logger
    @ .\logging.jl:603 [inlined]
 [13] (::VSCodeServer.var"#46#48"{Module, Expr, REPL.LineEditREPL, REPL.LineEdit.Prompt})()
    @ VSCodeServer ~\.vscode\extensions\julialang.language-julia-1.1.38\scripts\packages\VSCodeServer\src\repl.jl:100
 [14] #invokelatest#2
    @ .\essentials.jl:708 [inlined]
 [15] invokelatest(::Any)
    @ Base .\essentials.jl:706
 [16] macro expansion
    @ ~\.vscode\extensions\julialang.language-julia-1.1.38\scripts\packages\VSCodeServer\src\eval.jl:34 [inlined]
 [17] (::VSCodeServer.var"#60#61")()
    @ VSCodeServer .\task.jl:406

jmboehm / GLFixedEffectModels.jl

CategoricalVector not defined #17