diff --git a/nbclient/tests/files/JupyterWidgets.ipynb b/nbclient/tests/files/JupyterWidgets.ipynb
index fccfeb4e..5c0d1a34 100644
--- a/nbclient/tests/files/JupyterWidgets.ipynb
+++ b/nbclient/tests/files/JupyterWidgets.ipynb
@@ -23,7 +23,7 @@
    "source": [
     "import ipywidgets\n",
     "label = ipywidgets.Label('Hello World')\n",
-    "label"
+    "display(label)"
    ]
   },
   {
diff --git a/requirements-dev.txt b/requirements-dev.txt
index ec1b95ec..9888bb23 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -2,9 +2,10 @@ black
 check-manifest
 flake8
 ipykernel
-ipython<8.0.0
-ipywidgets<8.0.0
+ipython
+ipywidgets
 mypy
+nbconvert
 pip>=18.1
 pre-commit
 pytest>=4.1