I want to create a heatmap of a non-square matrix with square pixels. I'm trying to achieve this by setting a colsize of defined aspect. This however leads to somehow staggered pixels and strange effects, as CairoMakie seemingly draws the pixels larger than they actually are.

Some demo code and the corresponding PDF opened in inkscape:

fig = Figure(size = mm2pt.((83, 50)))
ax = Axis(fig[1, 1])
r = rand(20,30)
colsize!(fig.layout, 1, Aspect(1, size(r)[1] / size(r)[2]))
heatmap!(ax, r; colorrange = (0, 1))
save("deleteme.pdf", fig)

The problem:

Any idea how I can make the pixels square without this effect?

Makie 0.20.7, CairoMakie 0.11.8, julia 1.10