diff --git a/jupyterlab_widgets/src/manager.ts b/jupyterlab_widgets/src/manager.ts
index 977dc7e607..974a3ce7d3 100644
--- a/jupyterlab_widgets/src/manager.ts
+++ b/jupyterlab_widgets/src/manager.ts
@@ -53,7 +53,8 @@ export const WIDGET_STATE_MIMETYPE =
  */
 export abstract class LabWidgetManager
   extends ManagerBase
-  implements IDisposable {
+  implements IDisposable
+{
   constructor(rendermime: IRenderMimeRegistry) {
     super();
     this._rendermime = rendermime;
diff --git a/jupyterlab_widgets/src/renderer.ts b/jupyterlab_widgets/src/renderer.ts
index aed73c09cd..f5509ba9c6 100644
--- a/jupyterlab_widgets/src/renderer.ts
+++ b/jupyterlab_widgets/src/renderer.ts
@@ -17,7 +17,8 @@ import { DOMWidgetModel } from '@jupyter-widgets/base';
  */
 export class WidgetRenderer
   extends Panel
-  implements IRenderMime.IRenderer, IDisposable {
+  implements IRenderMime.IRenderer, IDisposable
+{
   constructor(options: IRenderMime.IRendererOptions, manager?: WidgetManager) {
     super();
     this.mimeType = options.mimeType;
diff --git a/jupyterlab_widgets/src/semvercache.ts b/jupyterlab_widgets/src/semvercache.ts
index 49aa49b43b..24412999b2 100644
--- a/jupyterlab_widgets/src/semvercache.ts
+++ b/jupyterlab_widgets/src/semvercache.ts
@@ -28,7 +28,6 @@ export class SemVerCache<T> {
     }
   }
 
-  private _cache: { [key: string]: { [version: string]: T } } = Object.create(
-    null
-  );
+  private _cache: { [key: string]: { [version: string]: T } } =
+    Object.create(null);
 }