message: click to mousedown to fix interaction
diff: @@ -332,7 +332,7 @@ export default async function embed(
  .append('a')
  .text(i18n.SOURCE_ACTION)
  .attr('href', '#')
  - .on('click', () => {
  + .on('mousedown', () => {
  viewSource(stringify(spec), opt.sourceHeader || '', opt.sourceFooter || '', mode);
  d3.event.preventDefault();
  });
  @@ -344,7 +344,7 @@ export default async function embed(
  .append('a')
  .text(i18n.COMPILED_ACTION)
  .attr('href', '#')
  - .on('click', () => {
  + .on('mousedown', () => {
  viewSource(stringify(vgSpec), opt.sourceHeader || '', opt.sourceFooter || '', 'vega');
  d3.event.preventDefault();
  });
  @@ -357,7 +357,7 @@ export default async function embed(
  .append('a')
  .text(i18n.EDITOR_ACTION)
  .attr('href', '#')
  - .on('click', () => {
  + .on('mousedown', () => {
  post(window, editorUrl, {
  config: config as Config,
  mode,
  