color range slider mask rect with Color.fill
color range slider mask rect with Color.fill

- so that rgba color is set as:
  `fill: ${rgb}` + `fill-opacity: ${alpha}`
  for compatibility with eps/pdf exports

iongroup/plotly.js,plotly/plotly.js,plotly/plotly.js,plotly/plotly.js,etpinard/plotly.js,asolagmbh/plotly.js,asolagmbh/plotly.js,etpinard/plotly.js,iongroup/plotly.js,asolagmbh/plotly.js,etpinard/plotly.js,plotly/plotly.js,iongroup/plotly.js,aburato/plotly.js,aburato/plotly.js