OptionalopaqueRender an eccentric bar at full opacity — a solid silhouette with an opaque hatch over it, instead of the default translucent one.
The default fill lets the surface show through, which reads well where a
bar sits on a chart's own tinted plot area against neighbouring bars. It
does NOT read well where a lone thin bar sits on the app surface with
nothing around it to compare against — the tracking app's per-rep chart
rows. Those pass opaque, which keeps the diagonal hatch (so eccentric
still reads as eccentric) but stops the bar from looking washed out.
Options for repBarFillStyle.