diff --git a/packages/htmlviewer-extension/package.json b/packages/htmlviewer-extension/package.json
index 89004dccbff1..9efbd4b3e651 100644
--- a/packages/htmlviewer-extension/package.json
+++ b/packages/htmlviewer-extension/package.json
@@ -36,7 +36,8 @@
     "@jupyterlab/application": "^2.0.0-alpha.4",
     "@jupyterlab/apputils": "^2.0.0-alpha.4",
     "@jupyterlab/docregistry": "^2.0.0-alpha.4",
-    "@jupyterlab/htmlviewer": "^2.0.0-alpha.4"
+    "@jupyterlab/htmlviewer": "^2.0.0-alpha.4",
+    "@jupyterlab/ui-components": "^2.0.0-alpha.4"
   },
   "devDependencies": {
     "rimraf": "~3.0.0",
diff --git a/packages/htmlviewer-extension/tsconfig.json b/packages/htmlviewer-extension/tsconfig.json
index 6a04d89ee1fd..55e1f5da685a 100644
--- a/packages/htmlviewer-extension/tsconfig.json
+++ b/packages/htmlviewer-extension/tsconfig.json
@@ -17,6 +17,9 @@
     },
     {
       "path": "../htmlviewer"
+    },
+    {
+      "path": "../ui-components"
     }
   ]
 }