State-timeline diagram, yellow for value <> zero, transparent color else.
Color scheme: From thresholds by value.
Thresholds: Base: transparent, 1: yellow
See screenshot: “Zeros” are shown as Black. Only none values are shown transparent but zero values should be transparent, too.
I think you should choose ‘from threshold’ under standard options → color scheme.
Single colors are colors for single entries and make no sense for state timeline. Transparency based on thresholds would make sense here, but seems to be not supported (yet?)
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