message: fix: Change downloadAsImage to use Superset theme
diff: import { SyntheticEvent } from 'react';
  import domToImage from 'dom-to-image-more';
  import kebabCase from 'lodash/kebabCase';
  -import { t } from '@superset-ui/core';
  +import { t, supersetTheme } from '@superset-ui/core';
  import { addWarningToast } from 'src/components/MessageToasts/actions';
  -/**
  - * @remark
  - * same as https://github.com/apache/superset/blob/c53bc4ddf9808a8bb6916bbe3cb31935d33a2420/superset-frontend/src/assets/stylesheets/less/variables.less#L34
  - */
  -const GRAY_BACKGROUND_COLOR = '#F5F5F5';
  -
  /**
  * generate a consistent file stem from a description and date
  *
  @@ -77,7 +71,7 @@ export default function downloadAsImage(
  return domToImage
  .toJpeg(elementToPrint, {
  quality: 0.95,
  - bgcolor: GRAY_BACKGROUND_COLOR,
  + bgcolor: supersetTheme.colors.grayscale.light4,
  filter,
  })
  .then(dataUrl => {
  