diff --git a/app/assets/javascripts/content_editor/services/autocomplete_helper.js b/app/assets/javascripts/content_editor/services/autocomplete_helper.js
index c5e29e1cd3f949bd7a0da02f24239e890f8d0fe7..4bafe486fef93d0562b3f97c6ecd8b83b967ef28 100644
--- a/app/assets/javascripts/content_editor/services/autocomplete_helper.js
+++ b/app/assets/javascripts/content_editor/services/autocomplete_helper.js
@@ -1,4 +1,4 @@
-import { identity, memoize, throttle } from 'lodash';
+import { identity, memoize, throttle, isEmpty } from 'lodash';
 import { initEmojiMap, getAllEmoji, searchEmoji } from '~/emoji';
 import { parsePikadayDate } from '~/lib/utils/datetime_utility';
 import axios from '~/lib/utils/axios_utils';
@@ -118,7 +118,10 @@ export function createDataSource({
 
 export default class AutocompleteHelper {
   constructor({ dataSourceUrls, sidebarMediator }) {
-    this.dataSourceUrls = dataSourceUrls;
+    this.dataSourceUrls = !isEmpty(dataSourceUrls)
+      ? dataSourceUrls
+      : gl.GfmAutoComplete?.dataSources;
+
     this.sidebarMediator = sidebarMediator;
 
     initEmojiMap();
diff --git a/spec/frontend/content_editor/services/autocomplete_helper_spec.js b/spec/frontend/content_editor/services/autocomplete_helper_spec.js
index 39b96798184953a8089dea1a1ecdad32f897c786..abbc60c228861535f8f958d43770bbcdda52725b 100644
--- a/spec/frontend/content_editor/services/autocomplete_helper_spec.js
+++ b/spec/frontend/content_editor/services/autocomplete_helper_spec.js
@@ -199,4 +199,17 @@ describe('AutocompleteHelper', () => {
       ).toMatchSnapshot();
     },
   );
+
+  it('loads default datasources if not passed', () => {
+    gl.GfmAutoComplete = {
+      dataSources: {
+        members: '/gitlab-org/gitlab-test/-/autocomplete_sources/members',
+      },
+    };
+    autocompleteHelper = new AutocompleteHelper({});
+
+    expect(autocompleteHelper.dataSourceUrls.members).toBe(
+      '/gitlab-org/gitlab-test/-/autocomplete_sources/members',
+    );
+  });
 });