OptionalalphaOffer an opacity control alongside the color.
OptionalblockRender full-width with no label row in schema-driven settings UIs
(weasel-ui PrefsForm honors this for leaves whose control brings
its own chrome).
Fallback when nothing is persisted.
Longer help text — shown in tooltips / a settings pane.
OptionalhiddenHide from a host app's settings UI by default.
Human-readable label.
OptionalpairRow-pairing hint for compact property UIs (weasel-ui
SelectionPanel): leaves sharing a pair id render side-by-side
on one row labeled with the pair string (e.g. 'Position' for
pose.x / pose.y). Purely presentational.
A whole
FillStyle, not a color inside one. Use it wherever the value is the tagged paint union — a solid color, a pattern, a gradient — rather than a hex string.Addressing
…fill.colorinstead readsundefinedoff a gradient (so the control shows its default and claims the text is black) and writes a hybrid{ fill: 'gradient', stops, color }that the renderer's structural'color' in paintchecks then paint flat solid. The union has to be edited as a union.