diff --git a/docs/data/data-grid/editing/CustomEditComponent.js b/docs/data/data-grid/editing/CustomEditComponent.js
index 8762b22fec6d8..d5d5cd3596fdf 100644
--- a/docs/data/data-grid/editing/CustomEditComponent.js
+++ b/docs/data/data-grid/editing/CustomEditComponent.js
@@ -11,7 +11,7 @@ function renderRating(params) {
 function RatingEditInputCell(props) {
   const { id, value, field, hasFocus } = props;
   const apiRef = useGridApiContext();
-  const ref = React.useRef();
+  const ref = React.useRef(null);
 
   const handleChange = (event, newValue) => {
     apiRef.current.setEditCellValue({ id, field, value: newValue });
diff --git a/docs/data/data-grid/editing/CustomEditComponent.tsx b/docs/data/data-grid/editing/CustomEditComponent.tsx
index dc0f84cd97f1e..63d036378717a 100644
--- a/docs/data/data-grid/editing/CustomEditComponent.tsx
+++ b/docs/data/data-grid/editing/CustomEditComponent.tsx
@@ -16,7 +16,7 @@ function renderRating(params: GridRenderCellParams<any, number>) {
 function RatingEditInputCell(props: GridRenderCellParams<any, number>) {
   const { id, value, field, hasFocus } = props;
   const apiRef = useGridApiContext();
-  const ref = React.useRef<HTMLElement>();
+  const ref = React.useRef<HTMLElement>(null);
 
   const handleChange = (event: React.SyntheticEvent, newValue: number | null) => {
     apiRef.current.setEditCellValue({ id, field, value: newValue });
diff --git a/docs/data/data-grid/performance/GridVisualization.js b/docs/data/data-grid/performance/GridVisualization.js
index b87db7d566d4d..012448e2fd472 100644
--- a/docs/data/data-grid/performance/GridVisualization.js
+++ b/docs/data/data-grid/performance/GridVisualization.js
@@ -6,7 +6,7 @@ import { useDemoData } from '@mui/x-data-grid-generator';
 
 const TraceUpdates = React.forwardRef((props, ref) => {
   const { Component, ...other } = props;
-  const rootRef = React.useRef();
+  const rootRef = React.useRef(null);
   const handleRef = useForkRef(rootRef, ref);
 
   React.useEffect(() => {
diff --git a/docs/data/data-grid/performance/GridVisualization.tsx b/docs/data/data-grid/performance/GridVisualization.tsx
index 51781f6abc4c5..f40abc5a5cc59 100644
--- a/docs/data/data-grid/performance/GridVisualization.tsx
+++ b/docs/data/data-grid/performance/GridVisualization.tsx
@@ -6,7 +6,7 @@ import { useDemoData } from '@mui/x-data-grid-generator';
 
 const TraceUpdates = React.forwardRef<any, any>((props, ref) => {
   const { Component, ...other } = props;
-  const rootRef = React.useRef<HTMLElement>();
+  const rootRef = React.useRef<HTMLElement>(null);
   const handleRef = useForkRef(rootRef, ref);
 
   React.useEffect(() => {