load SettingsOptions component lazily

src/plugins/vis_type_markdown/public/markdown_vis.ts

@@ -21,7 +21,7 @@ import { i18n } from '@kbn/i18n';
 
 import { MarkdownVisWrapper } from './markdown_vis_controller';
 import { MarkdownOptions } from './markdown_options';
-import { SettingsOptions } from './settings_options';
+import { SettingsOptions } from './settings_options_lazy';
 import { DefaultEditorSize } from '../../vis_default_editor/public';
 
 export const markdownVisDefinition = {

src/plugins/vis_type_markdown/public/settings_options.tsx

@@ -52,4 +52,6 @@ function SettingsOptions({ stateParams, setValue }: VisOptionsProps<MarkdownVisP
   );
 }
 
-export { SettingsOptions };
+// default export required for React.Lazy
+// eslint-disable-next-line import/no-default-export
+export { SettingsOptions as default };

src/plugins/vis_type_markdown/public/settings_options_lazy.tsx

@@ -0,0 +1,30 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import React, { lazy, Suspense } from 'react';
+import { EuiLoadingSpinner } from '@elastic/eui';
+
+// @ts-ignore
+const SettingsOptionsComponent = lazy(() => import('./settings_options'));
+
+export const SettingsOptions = (props: any) => (
+  <Suspense fallback={<EuiLoadingSpinner />}>
+    <SettingsOptionsComponent {...props} />
+  </Suspense>
+);