OptionalcolorDefaults to the row's valueColor, then color, then the theme text.
OptionalfieldWhich status-line switch owns this reading. Untagged readings are the
source's own last value, governed by statusLine.lastValueLabel.
OptionallabelDimmed prefix, e.g. O / H / Vol.
OptionalpriorityHigher values retain this whole reading on narrow rows. Series readings default to 1; status metadata ranks lower.
One reading on a legend row. Multi-plot sources show one per plot, each in that plot's own color (an MA ribbon's four averages, MACD's three lines): a single string in a single color cannot say which number is which.