Line visibility

const config = { type: 'line', data, options: { plugins: { annotation: { annotations: { annotation } } } } };

const config = {
  type: 'line',
  data,
  options: {
    plugins: {
      annotation: {
        annotations: {
          annotation
        }
      }
    }
  }
};

const annotation = { type: 'line', borderColor: 'black', borderWidth: 1, display: (ctx) => ctx.chart.isDatasetVisible(1), label: { enabled: true, content: 'Now', position: 'start' }, scaleID: 'x', value: 'July' };

const annotation = {
  type: 'line',
  borderColor: 'black',
  borderWidth: 1,
  display: (ctx) => ctx.chart.isDatasetVisible(1),
  label: {
    enabled: true,
    content: 'Now',
    position: 'start'
  },
  scaleID: 'x',
  value: 'July'
};

const DATA_COUNT = 6; const MIN = 10; const MAX = 100; Utils.srand(8); const jointValue = Utils.rand(MIN, MAX); const dataCfg = Utils.numbers({count: DATA_COUNT, min: MIN, max: MAX}); dataCfg.push(jointValue, NaN, NaN, NaN, NaN, NaN, NaN); const futureCfg = Utils.numbers({count: DATA_COUNT - 1, min: MIN, max: MAX}); futureCfg.splice(0, 0, NaN, NaN, NaN, NaN, NaN, NaN, jointValue); const data = { labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'], datasets: [{ data: dataCfg }, { data: futureCfg, borderDash: [6, 6] }] };

const DATA_COUNT = 6;
const MIN = 10;
const MAX = 100;
Utils.srand(8);
const jointValue = Utils.rand(MIN, MAX);
const dataCfg = Utils.numbers({count: DATA_COUNT, min: MIN, max: MAX});
dataCfg.push(jointValue, NaN, NaN, NaN, NaN, NaN, NaN);
const futureCfg = Utils.numbers({count: DATA_COUNT - 1, min: MIN, max: MAX});
futureCfg.splice(0, 0, NaN, NaN, NaN, NaN, NaN, NaN, jointValue);
const data = {
  labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'],
  datasets: [{
    data: dataCfg
  }, {
    data: futureCfg,
    borderDash: [6, 6]
  }]
};