Preserve page's scroll position

components/layout/Page.js

@@ -2,6 +2,25 @@ import React from 'react';
 import classNames from 'classnames';
 import styles from './Page.module.css';
 
-export default function Page({ className, children }) {
+export default class Page extends React.Component {
-  return <div className={classNames(styles.page, className)}>{children}</div>;
+  getSnapshotBeforeUpdate() {
+    if (window.pageXOffset === 0 && window.pageYOffset === 0) return null;
+
+    // Return the scrolled position as the snapshot value
+    return { x: window.pageXOffset, y: window.pageYOffset };
+  }
+
+  /* eslint-disable no-unused-vars */
+  componentDidUpdate(prevProps, prevState, snapshot) {
+    if (snapshot !== null) {
+      // Restore the scrolled position after re-rendering
+      window.scrollTo(snapshot.x, snapshot.y);
+    }
+  }
+  /* eslint-enable no-unused-vars */
+
+  render() {
+    const { className, children } = this.props;
+    return <div className={classNames(styles.page, className)}>{children}</div>;
+  }
 }