On Tue, 12 Apr 2016 18:45:00 -0700, Don Y wrote:

6% of men are red-green colorblind.

It's slightly more (~8%; higher with those of North European ancestry), but
more to the point, they never seem to complain much about how society
ignores them.

The worst case I can think of are colour-coded diodes where there are two
junctions in the same device so it can light up red, yellow, or green
depending on which leads are powered.

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