Backport PR #11010: Fix ignored promise leading to incorrect initial tooltip position (#11013)

Co-authored-by: Michał Krassowski <5832902+krassowski@users.noreply.github.com>

packages/tooltip/src/widget.ts

@@ -69,7 +69,10 @@ export class Tooltip extends Widget {
     }
 
     this._content = this._rendermime.createRenderer(mimeType);
-    void this._content.renderModel(model);
+    this._content
+      .renderModel(model)
+      .then(() => this._setGeometry())
+      .catch(error => console.error('tooltip rendering failed', error));
     this._content.addClass(CONTENT_CLASS);
     layout.addWidget(this._content);
   }