diff --git a/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.ts b/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.ts
index 3b026b3..8821725 100644
--- a/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.ts
+++ b/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.ts
@@ -15,6 +15,7 @@
  * limitations under the License.
  */
 import '../../../styles/shared-styles';
+import '../../shared/gr-tooltip/gr-tooltip';
 import {GrTooltip} from '../../shared/gr-tooltip/gr-tooltip';
 import {customElement, property} from '@polymer/decorators';
 import {flush} from '@polymer/polymer/lib/legacy/polymer.dom';