Hide/Remove/Replace widgets from Makie.jl reactive plots

Hello everyone, I have a question about Makie.
Just for context, I have a reactive plot that has a Makie.Colorbar, but when the Colorbar limits are equal it breaks.
So my question is:
Can I hide/remove the Colorbar or replace it with another widget in the Makie.on event?

MWE:

using GLMakie

function myplot(x, y, colors)
  fig = Figure()
  menu = Menu(fig[1, :], options=collect(propertynames(colors)))

  color = Observable{Any}()
  limits = Observable{Any}()

  c = first(colors)
  color[] = c
  limits[] = extrema(c)

  scatter(fig[2, 1], x, y; color)
  Colorbar(fig[2, 2]; limits)

  on(menu.selection) do name
    c = colors[name]
    color[] = c
    limits[] = extrema(c)
    # PROBLEM: if minimum(c) == maximum(c), hide, remove or replace Colorbar
  end

  fig
end

x = rand(1:9, 10)
y = rand(1:0, 10)
colors = (a=rand(1:5, 10), b=rand(5:9, 10))
myplot(x, y, colors) # works

colors = (a=rand(1:5, 10), b=fill(1, 10))
myplot(x, y, colors) # breaks