[BUG] Alpha applies to whole columns instead of individual indices in heatmap

[weymouth]

Details

See https://discourse.julialang.org/t/plots-jl-mask-values-in-heatmap/69223

I’m trying to gradually mask out values of a rectangular array in a heatmap using alpha, but

heatmap(rand(10,10),alpha=rand(10,10))

Applies the alpha to columns instead of individual indices.

Backends

This bug occurs on ( insert x below )

Backend	yes	no	untested
gr (default)	x
pyplot	x
plotlyjs	x
pgfplotsx	x
unicodeplots			x
inspectdr	x
gaston			x

Versions

Plots.jl version: Plots v1.22.3
Backend version (]st -m <backend(s)>):
Output of versioninfo():

[BeastyBlacksmith]

This example produces errors or wrong results on every backend :(